Speciality Polymers, Engineering Polymers and Commodity Polymers

COMMODITY POLYMERS, ENGINEERING POLYMERS AND SPECIALITY POLYMERS

MUHAMMAD REHAN ASHRAF NATIONAL TEXTILE UNIVERSITY Faisalabad

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TABLE OF CONTENTS 1 COMMODITY POLYMERS

1

1.1 POLYETHYLENE (PE)

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1.1.1 BRIEF INTRODUCTION

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1.1.2 PROPERTIES

2

1.1.3 APPLICATIONS

2

1.2 POLYPROPYLENE (PP)

2

1.2.1 BRIEF INTRODUCTION

2

1.2.2 PROPERTIES

3

1.2.3 APPLICATIONS

3

1.3 POLYSTYRENE (PS)

3

1.3.1 BRIEF INTRODUCTION

3

1.3.2 PROPERTIES

4

1.3.3 APPLICATIONS

4

1.4 POLYVINYL CHLORIDE (PVC)

4

1.4.1 BRIEF INTRODUCTION

4

1.4.2 PROPERTIES

5

1.4.3 APPLICATIONS

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1.5 HIGH-DENSITY POLYETHYLENE (HDPE)

5

1.5.1 BRIEF INTRODUCTION

5

1.5.2 PROPERTIES

6

1.5.3 APPLICATIONS

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1.6 POLY(METHYL METHACRYLATE) (PMMA)

6

1.6.1 BRIEF INTRODUCTION

6

1.6.2 PROPERTIES

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1.6.3 APPLICATIONS

7

1.7 POLYETHYLENE TEREPHTHALATE (PET)

7

1.7.1 BRIEF INTRODUCTION

7

1.7.2 PROPERTIES

8

1.7.3 APPLICATIONS

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1.8 POLY(METHYL ACRYLATE) (PMA)

8

1.8.1 BRIEF INTRODUCTION

8

1.8.2 PROPERTIES

9

1.8.3 APPLICATIONS

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1.9 LINEAR LOW-DENSITY POLYETHYLENE (LLDPE)

9

1.9.1 BRIEF INTRODUCTION

9

1.9.2 PROPERTIES

10

1.9.3 APPLICATIONS

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1.10 LOW-DENSITY POLYETHYLENE (LDPE)

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1.10.1 BRIEF INTRODUCTION

10

1.10.2 PROPERTIES

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1.10.3 APPLICATIONS

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2 ENGINEERING POLYMERS

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2.1 ULTRA HIGH MOLECULAR WEIGHT PE (UHMW-PE)

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2.1.1 BRIEF INTRODUCTION

12

2.1.2 PROPERTIES

12

2.1.3 APPLICATIONS

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2.2 POLYTETRAFLUOROETHYLENE (PTFE)

13

2.2.1 BRIEF INTRODUCTION

13

2.2.2 PROPERTIES

13

2.2.3 APPLICATIONS

14

2.3 POLYSULFONE

14

2.3.1 BRIEF INTRODUCTION

14

2.3.2 PROPERTIES

14

2.3.3 APPLICATIONS

14

2.4 POLYOXYMETHYLENE

15

2.4.1 BRIEF INTRODUCTION

15

2.4.2 PROPERTIES

15

2.4.3 APPLICATIONS

15

2.5 POLYBUTYLENE TEREPHTHALATE (PBT)

16

2.5.1 BRIEF INTRODUCTION

16

2.5.2 PROPERTIES

16

2.5.3 APPLICATIONS

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2.6 POLYETHER ETHER KETONE (PEEK)

16

2.6.1 BRIEF INTRODUCTION

16

2.6.2 PROPERTIES

16

2.6.3 APPLICATIONS

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2.7 NYLON 6-6

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2.7.1 BRIEF INTRODUCTION

17

2.7.2 PROPERTIES

17

2.7.3 APPLICATIONS

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2.8 ACRYLONITRILE BUTADIENE STYRENE (ABS)

18

2.8.1 BRIEF INTRODUCTION

18

2.8.2 PROPERTIES

18

2.8.3 APPLICATIONS

18

2.9 POLYPHENYLENE OXIDE (PPO)

18

2.9.1 BRIEF INTRODUCTION

19

2.9.2 PROPERTIES

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2.9.3 APPLICATIONS

19

2.10 POLYETHYLENE TEREPHTHALATE (PET)

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2.10.1 BRIEF INTRODUCTION

19

2.10.2 PROPERTIES

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2.10.3 APPLICATIONS

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3 SPECIALTY POLYMERS

20

3.1 LIQUID CRYSTAL POLYMERS (VECTRAN)

21

3.1.1 BRIEF INTRODUCTION

21

3.1.2 PROPERTIES

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3.1.3 APPLICATIONS

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3.2 ELECTROLUMINESCENT POLYMERS (POLYPHENYLENE-VINYLENE (PPV))

22

3.2.1 BRIEF INTRODUCTION

22

3.2.2 PROPERTIES

22

3.2.3 APPLICATIONS

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3.3 GLASS FIBRE REINFORCED POLYMER (GLASS FRP)

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3.3.1 BRIEF INTRODUCTION

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3.3.2 PROPERTIES

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3.3.3 APPLICATIONS

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3.4 CARBON FIBRE REINFORCED POLYMER (CARBON FRP)

23

3.4.1 BRIEF INTRODUCTION

23

3.4.2 PROPERTIES

23

3.4.3 APPLICATIONS

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3.5 POLYHYDROXYBUTARATE-HYDROXYVALARATE (PHBV)

24

3.5.1 BRIEF INTRODUCTION

24

3.5.2 PROPERTIES

24

3.5.3 APPLICATIONS

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3.6 POLYCARBONATE (THERMOPLASTIC POLYMER)

24

3.6.1 BRIEF INTRODUCTION

25

3.6.2 PROPERTIES

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3.6.3 APPLICATIONS

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3.7 BIODEGRADEABLE POLYMER (POLYHYDROXYVALARATE)

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3.7.1 BRIEF INTRODUCTION

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3.7.2 APPLICATIONS

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3.8 KEVLAR

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3.8.1 BRIEF INTRODUCTION

26

3.8.2 PROPERTIES

27

3.8.3 APPLICATIONS

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3.9 POLYHYDROXYBUTYRATE (PHB)

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3.9.1 BRIEF INTRODUCTION

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3.9.2 PROPERTIES

28

3.9.3 APPLICATIONS

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3.10 CONDUCTING POLYMER (POLYPYRROLE (PPY))

28

3.10.1 BRIEF INTRODUCTION

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3.10.2 PROPERTIES

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3.10.3 APPLICATIONS

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4 REFERENCES

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LIST OF FIGURES FIGURE 1: REPEATING UNIT OF PE _________________________________________________ 2 FIGURE 2: REPEATING UNIT OF PP _________________________________________________ 2 FIGURE 3: REPEATING UNIT OF PS _________________________________________________ 4 FIGURE 4: REPEATING UNIT OF PVC _______________________________________________ 5 FIGURE 5: RECYCLING SYMBOL OF HDPE ___________________________________________ 6 FIGURE 6: REPEATING UNIT OF PMMA ______________________________________________ 7 FIGURE 7: REPEATING UNIT OF PET________________________________________________ 8 FIGURE 8: REPEATING UNIT OF PMA _______________________________________________ 9 FIGURE 9: LLDPE GRANULES ___________________________________________________ 10 FIGURE 10: RECYCLING NUMBER OF LDPE _________________________________________ 11 FIGURE 11: REPEATING UNIT OF UHMW-PE ________________________________________ 12 FIGURE 12: REPEATING UNIT OF POLYTETRAFLUOROETHYLENE __________________________ 13 FIGURE 13: REPEATING UNIT OF POLYSULFONE ______________________________________ 14 FIGURE 14: REPEATING UNIT OF POM _____________________________________________ 15 FIGURE 15: REPEATING UNIT OF PBT______________________________________________ 16 FIGURE 16: REPEATING UNIT OF NYLON 6,6 _________________________________________ 17 FIGURE 17: MONOMERS IN ABS POLYMER __________________________________________ 18 FIGURE 18: REPEATING UNIT OF PPO _____________________________________________ 19 FIGURE 19: REPEATING UNIT OF PET______________________________________________ 20 FIGURE 20 : MOLECULAR STRUCTURE OF LCP VECTRAN _______________________________ 21 FIGURE 21 : MOLECULAR STRUCTURE OF PPV _______________________________________ 22 FIGURE 22: REPEATING UNIT OF PHBV ____________________________________________ 24 FIGURE 23: PREPARATION OF POLYCARBONATE ______________________________________ 25 FIGURE 24: BIODEGRADABLE PLASTIC _____________________________________________ 26 FIGURE 25: KEVLAR ___________________________________________________________ 27 FIGURE 26: POLYHYROXYBUTYRATE ______________________________________________ 28 FIGURE 27: MOLECULAR STRUCTURE OF POLYPYRROLE________________________________ 28

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COMMODITY POLYMERS, ENGINEERING POLYMERS AND SPECIALITY POLYMERS 1 COMMODITY POLYMERS Commodity polymers are basically those polymers which are found in our daily life usage from low value items such as plastic bags to high value items which doesn’t require precise and high mechanical properties. Commodity polymers are utilized for bulk and high-volume ends (like containers and packaging). Such polymers exhibit relatively low mechanical properties and are of low cost. The range of products includes Plates, Cups, Carrying Trays, Medical Trays, Containers, Seeding Trays, Printed Material and other disposable items. Commodity polymers are polymers that are used in high volume and wide range of applications such as photographic and magnetic tape, clothing, beverage, trash containers, film for packaging, and a variety of household products where mechanical properties and service environments are not critical. Most of the commodity polymers are made by addition polymerization and those commodity polymers are thermoplastic polymers. Commodity thermoplastics account for almost 80% of all thermoplastics. Commodity polymers are usually cheap and easily available as compared to engineering polymers and specialty polymers. Examples of commodity polymers are Polyethylene (PE), Polypropylene (PP), Polystyrene (PS), Poly(vinyl chloride) (PVC), Polytetrafluoroethylene (PTFE), Poly(methyl methacrylate) (PMMA), Poly(ethylene terephthalate) (PET), and more.

1.1 POLYETHYLENE (PE) 1.1.1 BRIEF INTRODUCTION Polyethylene is a thermoplastic polymer consisting of long hydrocarbon chains and a most common plastic. The major differences of PE molecules occur during polymerization process in the form of a branched or linear polymer. IUPAC Name: Polyethene or Poly(methylene) Repeating Unit: (C2H4)n

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Figure 1: Repeating Unit of PE

1.1.2 PROPERTIES        

It is a high molecular weight, relatively insensitive to most solvent (used for chemical reaction vessels or pipe). Amorphous density at 25oC is 0.855 g/cm3. Crystalline density at 25oC is 1.00 g/cm3. Tg is -78ºC and Tm is typically 105-115ºC. The thermal conductivity is good, however Tm of PE is low - limited applications at high temperature. Considerable stiffness and strength/toughness. Resistant to chemicals. Low cost polymer, ease of forming, and permeability to gas and ease of processing.

1.1.3 APPLICATIONS  

Polyethene is used to make large water pipes. Its uses include film, packaging and containers, from bottles to buckets.

1.2 POLYPROPYLENE (PP) 1.2.1 BRIEF INTRODUCTION Polypropylene (PP) is a thermoplastic polymer used in a wide variety of applications. Polypropylene is the second most important plastic with revenues expected to exceed US$145 billion by 2019. The demand for this material was growing at a rate of 4.4% per year between 2004 and 2012. IUPAC Name: poly(propene)

Figure 2: Repeating Unit of PP

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1.2.2 PROPERTIES 

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Most commercial polypropylene is isotactic and has an intermediate level of crystallinity between that of low-density polyethylene (LDPE) and high-density polyethylene (HDPE). Amorphous density at 25ºC is 0.85 g/cm3. Crystalline density at 25oC: 0.95 g/cm3. Tg is -10ºC and Tm is 173ºC. Tough and flexible, especially when copolymerized with ethylene. Polypropylene has good resistance to fatigue. Polypropylene is reasonably economical, and can be made translucent.

1.2.3 APPLICATIONS 

  

Used in packaging and labeling, textiles (e.g., ropes, thermal underwear and carpets), stationery, plastic parts and reusable containers of various types, laboratory equipment, loudspeakers, automotive components, and polymer banknotes. Its most common medical use is in the synthetic, nonabsorbable suture Prolene, manufactured by Ethicon Inc. Polypropylene has been used in hernia and pelvic organ prolapse repair operations to protect the body from new hernias in the same location. Many plastic daily life items are made from polypropylene.

1.3 POLYSTYRENE (PS) 1.3.1 BRIEF INTRODUCTION Polystyrene (PS) is a synthetic aromatic polymer made from the monomer styrene, a liquid petrochemical. Polystyrene can be rigid or foamed. In chemical terms, polystyrene is a long chain hydrocarbon wherein alternating carbon centers are attached to phenyl groups (the name given to the aromatic ring benzene). Polystyrene is a vinyl polymer or hard plastic made from monomer styrene, a liquid extracted from petroleum products. IUPAC Name: Poly(1-phenylethylene)

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Figure 3: Repeating Unit of PS

1.3.2 PROPERTIES     

Polystyrenes is a colorless polymer that is available in sheet and pellet form. Amorphous density at 25ºC is 1.05 g/cm3. It has a Tg of 100ºC. It is also of low impact strength. It has poor chemical resistance and weather ability.

1.3.3 APPLICATIONS    

It is used in the manufacture of computer cases and as housings of items such as hairdryers, TVs and kitchen appliances. Polystyrene is an inexpensive hard plastic used for making disposable cutlery (Styrofoam) and a wide variety of plastic items. It is used as a building material, in electrical appliances including CDs and DVD cases. Clear plastic drinking cups are made of polystyrene.

1.4 POLYVINYL CHLORIDE (PVC) 1.4.1 BRIEF INTRODUCTION Poly(vinyl chloride), commonly abbreviated PVC, is the third-most widely produced polymer, after polyethylene and polypropylene. PVC is used in construction because it is more effective than traditional materials such as copper, iron or wood in pipe and profile applications. IUPAC Name: poly(1-chloroethylene)

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Figure 4: Repeating Unit of PVC

1.4.2 PROPERTIES       

Pure poly(vinyl chloride) is a white, brittle solid. Amorphous density at 25oC is 1.385 g/cm3. Crystalline density at 25oC is 1.52 g/cm3. Tg is 85oC and Tm is 240oC. Mechanical properties decrease with increasing temperature. PVC has high hardness and mechanical properties which enhance with the molecular weight increasing, but decrease with the temperature increasing. PVC is a polymer with good insulation properties.

1.4.3 APPLICATIONS    

It is used for sewerage pipes and other pipe applications where cost or vulnerability to corrosion limit the use of metal. It is a popular material for window and door frames. By adding plasticizers, it can become flexible enough to be used in cabling applications as a wire insulator. Roughly half of the world's polyvinyl chloride resin manufactured annually is used for producing pipes for municipal and industrial applications.

1.5 HIGH-DENSITY POLYETHYLENE (HDPE) 1.5.1 BRIEF INTRODUCTION High-density polyethylene (HDPE) or polyethylene high-density (PEHD) is a polyethylene thermoplastic made from petroleum. Known for its large strength to density ratio, HDPE is commonly used in the production of plastic bottles, corrosion-resistant piping, geomembranes, and plastic lumber. HDPE is commonly recycled, and has the number "2" as its recycling symbol.

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Figure 5: Recycling Symbol of HDPE

1.5.2 PROPERTIES      

HDPE is known for its large strength to density ratio. Density of HDPE can range from 0.93 to 0.97 g/cm3. Tg is -78°C and Tm is 100°C. It is also harder and more opaque and can withstand somewhat higher temperatures (120 °C/ 248 °F for short periods, 110 °C /230 °F continuously). HDPE has a high tensile strength. High-density polyethylene, unlike polypropylene, cannot withstand normally required autoclaving conditions.

1.5.3 APPLICATIONS     

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Bottle caps, Food storage containers and Heat-resistant fireworks mortars. Hard hats, Natural gas distribution pipe systems, Fireworks Plastic bags Plastic bottles suitable both for recycling (such as milk jugs) or re-use. Plastic lumber, Plastic surgery (skeletal and facial reconstruction), Stone paper, Storage sheds, Telecom ducts, Water pipes for domestic water supply and agricultural processes. Wood plastic composites (utilizing recycled polymers).

1.6 POLY(METHYL METHACRYLATE) (PMMA) 1.6.1 BRIEF INTRODUCTION Poly(methyl methacrylate) (PMMA) is a transparent thermoplastic, often used as a lightweight or shatter-resistant alternative to glass. Although it is not technically a type of glass, the substance has sometimes historically been called acrylic glass. Chemically, it is the synthetic polymer of methyl methacrylate. IUPAC Name: Poly(methyl 2-methylpropenoate)

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Figure 6: Repeating Unit of PMMA

1.6.2 PROPERTIES     

PMMA is a strong and lightweight material. It has a density of 1.17–1.20 g/cm3. Tg is 114°C and Tm is 460°C. It also has good impact strength, higher than both glass and polystyrene. Poor resistance to chemicals.

1.6.3 APPLICATIONS 

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 

1.7

PMMA is a versatile material and has been used in a wide range of fields and applications such as: rear-lights and instrument clusters for vehicles, appliances and lenses for glasses. PMMA in the form of sheets affords shatter resistant panels for building windows, skylights, bullet proof security barriers, signs & displays, sanitary ware (bathtubs), LCD screens, furniture and many other applications. It is also used for coating polymers. Methacrylate polymers are used extensively in medical and dental applications.

POLYETHYLENE TEREPHTHALATE (PET)

1.7.1 BRIEF INTRODUCTION Polyethylene terephthalate (sometimes written poly(ethylene terephthalate)), commonly abbreviated PET or PETE is a thermoplastic polymer resin of the polyester family and is used in synthetic fibers; beverage, food and other liquid containers; thermoforming applications; and engineering resins often in combination with glass fiber.

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Figure 7: Repeating Unit of PET

It may also be referred to by the brand name Dacron; in Britain, Terylene; or, in Russia and former Soviet Union, Lavsan. PET is referred to by its common name, "polyester," whereas the acronym "PET" is generally used in relation to packaging.

1.7.2 PROPERTIES      

Amorphous density at 25oC is 1.33 g/cm3. Crystalline density at 25oC is 1.50 g/cm3. Tg is 76oC and Tm is 250oC. PET in its natural state is a colorless, semi-crystalline resin. PET can be semi-rigid to rigid, and it is very lightweight. It is strong and impact-resistant.

1.7.3 APPLICATIONS    

PET is an excellent water and moisture barrier material. Plastic bottles made from PET are widely used for soft drinks. Its properties are useful in many applications, including flexible food packaging and thermal insulation such as "space blankets". Because of its high mechanical strength, PET film is often used in tape applications, such as the carrier for magnetic tape or backing for pressure-sensitive adhesive tapes.

1.8 POLY(METHYL ACRYLATE) (PMA) 1.8.1 BRIEF INTRODUCTION Poly(methyl acrylate) (PMA) is a hydrophobic synthetic acrylate polymer. PMA, though softer than polymethyl methacrylate (PMMA).

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Figure 8: Repeating Unit of PMA

1.8.2 PROPERTIES     

Amorphous density at 25oC is 1.22 g/cm3. High-energy radiation leads to cross linking in PMA. Glass transition temperature Tg is about 9 degree Celsius. PMA is water-sensitive and unlike PMMA, is not stable against alkalis. PMA is tough, leathery, and flexible.

1.8.3 APPLICATIONS  

It is used as macro initiator to initiate the copolymerization of HEMA and DMAEMA. Also used in leather finishing and textiles.

1.9 LINEAR LOW-DENSITY POLYETHYLENE (LLDPE) 1.9.1 BRIEF INTRODUCTION LLDPE is a derivative of PE which is commonly made by copolymerization of ethylene with longer-chain olefins. LLDPE doesn’t have long chain branches as opposed to its counterpart, LDPE. The linearity of LLDPE results from the different manufacturing processes of LLDPE and LDPE. In general, LLDPE is produced at lower temperatures and pressures by copolymerization of ethylene and such higher alpha-olefins as butene, hexene, or octene.

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Figure 9: LLDPE Granules

1.9.2 PROPERTIES      

LLDPE is linear in structure. Density is in the range of 0.915–0.925 g/cm3. Tg is 22 to 60ºC and Tm is 120 to 160ºC. LLDPE has higher tensile strength than LDPE, it exhibits higher impact and puncture resistance than LDPE. It has higher toughness. It has good electrical properties.

1.9.3 APPLICATIONS 

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It is used for plastic bags and sheets (where it allows using lower thickness than comparable LDPE), plastic wrap, stretch wrap, pouches, toys, covers, lids, pipes, buckets and containers, covering of cables and geomembranes. LLDPE is used in packaging, particularly film for bags and sheets. Used in agricultural films, saran wrap, and bubble wrap. Cable covering, toys, lids, buckets, containers and pipe.

1.10 LOW-DENSITY POLYETHYLENE (LDPE) 1.10.1

BRIEF INTRODUCTION

Low-density polyethylene (LDPE) is a thermoplastic made from the monomer ethylene. LDPE has a high degree of short and long chain branching.

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Figure 10: Recycling Number of LDPE

1.10.2        

LDPE has a high degree of short and long chain branching. Density ranges from 0.910–0.940 g/cm3. It is not reactive at room temperatures. It can withstand temperatures of 80 °C continuously and 95 °C for a short time. It is quite flexible, and tough but breakable Its tensile strength is lower, and its resilience is higher. Good resistance (minor attack) to aldehydes, ketones and vegetable oils Poor resistance, and not recommended for use with halogenated hydrocarbons.

1.10.3 

    

PROPERTIES

APPLICATIONS

LDPE is widely used for manufacturing various containers, dispensing bottles, wash bottles, tubing, plastic bags for computer components, and various molded laboratory equipment. Its most common use is in plastic bags. Trays and general purpose containers Corrosion-resistant work surfaces Parts that need to be weldable and machinable. Plastic wraps

2 ENGINEERING POLYMERS Engineering polymers are materials with exceptional mechanical properties such as stiffness, toughness, and low creep that make them valuable in the manufacture of structural products like gears, bearings, electronic devices, and auto parts. Engineering polymers are a group of polymers that have better mechanical and/or thermal properties than the more widely used commodity polymers (such as polystyrene, PVC, polypropylene and polyethylene). Being more expensive, engineering polymers are produced in lower quantities and tend to be used for smaller objects or low-volume applications (such as mechanical parts), rather than for bulk and high-volume ends (like containers and packaging). These plastics

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normally are not available to the public and frequently are available only to manufacturers in raw material form in order to be melted and molded into end products. The term usually refers to thermoplastic materials rather than thermosetting ones. Examples of engineering plastics include acrylonitrile butadiene styrene (ABS), used for car bumpers, dashboard trim and Lego bricks; polycarbonates, used in motorcycle helmets; and polyamides (nylons), used for skis and ski boots. Engineering polymers have gradually replaced traditional engineering materials such as wood or metal in many applications. Besides equaling or surpassing them in weight/strength and other properties, engineering polymers are much easier to manufacture, especially in complicated shapes.

2.1 ULTRA HIGH MOLECULAR WEIGHT PE (UHMW-PE) 2.1.1 BRIEF INTRODUCTION Ultra-high-molecular-weight polyethylene (UHMWPE, UHMW) is a subset of the thermoplastic polyethylene. Also known as high-modulus polyethylene, (HMPE), or highperformance polyethylene (HPPE), it has extremely long chains. The longer chain serves to transfer load more effectively to the polymer backbone by strengthening intermolecular interactions. This results in a very tough material, with the highest impact strength of any thermoplastic presently made.

Figure 11: Repeating Unit of UHMW-PE

2.1.2 PROPERTIES       

UHMWPE is odorless, tasteless, nontoxic and self-lubricating. Amorphous density at 25oC is 0.855 g/cm3. Crystalline density at 25oC is 1.00 g/cm3. Tg is -87oC and Tm is 103oC. Resistant to high temperature. Its coefficient of friction is significantly lower than that of nylon and acetal, and is comparable to that of polytetrafluoroethylene (PTFE, Teflon). It is highly resistant to corrosive chemicals except oxidizing acids.

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UHMWPE has better abrasion resistance than PTFE.

2.1.3 APPLICATIONS     

UHMWPE sheet has been used as synthetic ice in ice rinks where ambient temperatures or energy costs make it impractical to create and maintain normal ice. UHMWPE sheet is also cut into small blocks to be used as a brake pad material for mountain bike trials rim brakes. UHMWPE is a successful biomaterial for use in hip, knee, and for spine implants. UHMWPE is also used in the manufacture of Hydraulic Seals and Bearings. UHMWPE fibers are used in armor, in particular, personal armor and on occasion as vehicle armor, cut-resistant gloves and bow strings.

2.2 POLYTETRAFLUOROETHYLENE (PTFE) 2.2.1 BRIEF INTRODUCTION Polytetrafluoroethylene (PTFE) is a synthetic fluoropolymer of tetrafluoroethylene that has numerous applications. The best known brand name of PTFE is Teflon by DuPont Co. IUPAC Name: poly(1,1,2 ,2 -tetrafluoroethylene) PTFE is produced by free-radical polymerization of tetrafluoroethylene. The net equation is: n F2C=CF2 → 1/n —{ F2C—CF2}n—

Figure 12: Repeating Unit of Polytetrafluoroethylene

2.2.2 PROPERTIES    

PTFE is a thermoplastic polymer, which is a white solid at room temperature. Density of PTFE is about 2200 kg/m3. Tm is about 327ºC. PTFE has one of the lowest coefficients of friction against any solid.

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 

It maintains high strength, toughness and self-lubrication at low temperatures down to −268.15 °C and good flexibility at temperatures above −79 °C. It is very non-reactive, partly because of the strength of carbon–fluorine bonds.

2.2.3 APPLICATIONS    

PTFE is used as a non-stick coating for pans and other cookware. It is often used in containers and pipework for reactive and corrosive chemicals. Where used as a lubricant, PTFE reduces friction, wear and energy consumption of machinery. It is also commonly used as a graft material in surgical interventions. The major application of PTFE, consuming about 50% of production, is for wiring in aerospace and computer applications (e.g. hookup wire, coaxial cables).

2.3 POLYSULFONE 2.3.1 BRIEF INTRODUCTION Polysulfone describes a family of thermoplastic polymers. These polymers are known for their toughness and stability at high temperatures. They contain the subunit arylSO2-aryl, the defining feature of which is the sulfone group.

Figure 13: Repeating Unit of Polysulfone

Due to the high cost of raw materials and processing, polysulfones are used in specialty applications and often are a superior replacement for polycarbonates.

2.3.2 PROPERTIES     

Its Tg is 185 °C. Mechanically, polysulfone has high compaction resistance, recommending its use under high pressures. These polymers are rigid, high-strength, and transparent. Polysulfone is highly resistant to mineral acids, alkali, and electrolytes, in pH ranging from 2 to 13. Polysulfone has one of the highest service temperature of all melt-process able thermoplastics.

2.3.3 APPLICATIONS

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Its resistance to high temperatures gives it a role of a flame retardant, without compromising its strength that usually results from addition of flame retardants. These polymers are also used in the automotive and electronic industries. Filter cartridges made from polysulfone membranes offer extremely high flow rates at very low differential pressures. Polysulfone is used as a dielectric in capacitors.

2.4 POLYOXYMETHYLENE 2.4.1 BRIEF INTRODUCTION Polyoxymethylene (POM), also known as acetal, polyacetal and polyformaldehyde is an engineering thermoplastic used in precision parts requiring high stiffness, low friction and excellent dimensional stability. As with many other synthetic polymers, it is produced by different chemical firms with slightly different formulas and sold variously by such names as Delrin, Celcon, Duracon and Hostaform.

Figure 14: Repeating Unit of POM

2.4.2 PROPERTIES      

Amorphous density at 25oC is 1.25 g/cm3. Crystalline density at 25oC is 1.54 g/cm3. Tg is -30oC and Tm is 183oC. High heat resistance. High abrasion resistance. Good electrical and dielectric properties.

2.4.3 APPLICATIONS      

The material is widely used in the automotive and consumer electronics industry. The M16 rifle's stock and other parts are made of it. Insulin pen and Metered dose inhalers (MDI). Hardware, locks, handles, hinges. Packaging: aerosol cans, vehicle tanks. Clothing: zippers.

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2.5 POLYBUTYLENE TEREPHTHALATE (PBT) 2.5.1 BRIEF INTRODUCTION Polybutylene terephthalate (PBT) is a thermoplastic engineering polymer that is used as an insulator in the electrical and electronics industries. It is a thermoplastic (semi)crystalline polymer, and a type of polyester. IUPAC Name: Poly(oxy-1,4-butanediyloxycarbonyl-1,4-phenylenecarbonyl)

Figure 15: Repeating Unit of PBT

2.5.2 PROPERTIES    

PBT can be treated with flame retardants to make it noncombustible. Heat-resistant up to 150 °C Mechanically strong, slightly lower strength and rigidity. Slightly better impact resistance

2.5.3 APPLICATIONS 

  

Polybutylene terephthalate is used for housings in electrical engineering, but also in automotive construction as plug connectors and in households for example in showerheads or irons. It is also found processed into fibers in toothbrushes and is used in the keycaps of some mechanical keyboards because of its resistance to wear. PBT can also be made into yarn. On account of its chlorine resistance, it is found especially in swimwear.

2.6 POLYETHER ETHER KETONE (PEEK) 2.6.1 BRIEF INTRODUCTION Polyether ether ketone (PEEK) is a colorless organic polymer thermoplastic in the polyaryletherketone (PAEK) family, used in engineering applications.

2.6.2 PROPERTIES

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   

PEEK is a semi crystalline thermoplastic with excellent mechanical and chemical resistance properties that are retained to high temperatures. Tg is 143 °C and Tm is 343 °C. It is highly resistant to thermal degradation as well as attack by both organic and aqueous environments. Excellent mechanical properties.

2.6.3 APPLICATIONS     

PEEK is used to fabricate items used in demanding applications, including bearings, piston parts, pumps, HPLC columns, compressor plate valves, and cable insulation. It is one of the few plastics compatible with ultra-high vacuum applications. PEEK is considered an advanced biomaterial used in medical implants. It is finding increased use in spinal fusion devices and reinforcing rods. It is extensively used in the aerospace, automotive, and chemical process industries.

2.7 NYLON 6-6 2.7.1 BRIEF INTRODUCTION Nylon 6-6, also referred to as nylon 6,6, is a polyamide from nylon class. The polymer is made of hexamethylenediamine and adipic acid, which give nylon 6-6 a total of 12 carbon atoms in each repeating unit, and its name: IUPAC Name: Poly[imino (1,6-dioxohexamethylene) imnohexamethylene]

Figure 16: Repeating Unit of Nylon 6,6

2.7.2 PROPERTIES     

Amorphous density at 25oC is 1.07 g/cm3. Crystalline density at 25oC is 1.24 g/cm3. Tg is 50oC and Tm is 255oC. Good mechanical strength and great rigidity. They are wrinkle-proof and highly resistant to abrasion and chemicals such as acids and alkalis.

2.7.3 APPLICATIONS

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  

It is used for ball bearing cages, electro-insulating elements, pipes, profiles and various machine parts. Other popular applications are: carpet fibres, apparel, airbags, tyres, zip ties, ropes, conveyor belts, hoses and the outer layer of turnout blankets. Nylon 6-6 is also a popular guitar nut material.

2.8 ACRYLONITRILE BUTADIENE STYRENE (ABS) 2.8.1 BRIEF INTRODUCTION Acrylonitrile butadiene styrene (ABS) is a common thermoplastic. Its glass transition temperature is approximately 105 °C. ABS is amorphous and therefore has no true melting point. ABS is a terpolymer made by polymerizing styrene and acrylonitrile in the presence of polybutadiene.

Figure 17: Monomers in ABS Polymer

2.8.2 PROPERTIES   

The styrene gives the plastic a shiny, impervious surface. High impact resistance and toughness. The polybutadiene, a rubbery substance, provides resilience even at low temperatures.

2.8.3 APPLICATIONS    

Lego bricks are made from ABS. Household and consumer goods are the major consumers of acrylonitrile butadiene styrene (ABS). ABS plastic ground down to an average diameter of less than 1 micrometer is used as the colorant in some tattoo inks. Tattoo inks that use ABS are extremely vivid. ABS is also commonly used in rapid prototyping extrusion-based 3D printers.

2.9 POLYPHENYLENE OXIDE (PPO)

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2.9.1 BRIEF INTRODUCTION Poly(p-phenylene oxide) (PPO) or poly(p-phenylene ether) (PPE) is a high-temperature thermoplastic. It is rarely used in its pure form due to difficulties in processing. It is mainly used as blend with polystyrene, high impact styrene-butadiene copolymer or polyamide.

Figure 18: Repeating Unit of PPO

2.9.2 PROPERTIES  

PPO is an amorphous high-performance plastic. Tg is 215 °C, but it can be varied by mixing with polystyrene.

2.9.3 APPLICATIONS  

PPE blends are used for structural parts, electronics, household and automotive items that depend on high heat resistance, dimensional stability and accuracy. They are also used in medicine for sterilizable instruments made of plastic.

2.10 POLYETHYLENE TEREPHTHALATE (PET) 2.10.1

BRIEF INTRODUCTION

Polyethylene terephthalate (sometimes written poly(ethylene terephthalate)), commonly abbreviated PET or PETE is a thermoplastic polymer resin of the polyester family and is used in synthetic fibers; beverage, food and other liquid containers; thermoforming applications; and engineering resins often in combination with glass fiber.

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Figure 19: Repeating Unit of PET

It may also be referred to by the brand name Dacron; in Britain, Terylene; or, in Russia and former Soviet Union, Lavsan. PET is referred to by its common name, "polyester," whereas the acronym "PET" is generally used in relation to packaging.

2.10.2      

Amorphous density at 25oC is 1.33 g/cm3. Crystalline density at 25oC is 1.50 g/cm3. Tg is 76oC and Tm is 250oC. PET in its natural state is a colorless, semi-crystalline resin. PET can be semi-rigid to rigid, and it is very lightweight. It is strong and impact-resistant.

2.10.3    



PROPERTIES

APPLICATIONS

PET is an excellent water and moisture barrier material. Plastic bottles made from PET are widely used for soft drinks. Its properties are useful in many applications, including flexible food packaging and thermal insulation such as "space blankets". Because of its high mechanical strength, PET film is often used in tape applications, such as the carrier for magnetic tape or backing for pressure-sensitive adhesive tapes. Non-oriented PET sheet can be thermoformed to make packaging trays and blisters.

3 SPECIALTY POLYMERS Specialty polymers are polymers having properties and characteristics specially engineered for specific purposes. They are ranged from mono-functional to multifunctional polymers. Specialty polymers are specifically designed to serve a specific purpose.

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They are made by keeping in mind where they are to be used, which chemical and mechanical properties are to be needed and how they to be shaped are. Every intricate detail is taken into consideration and their development is very sensitive if we talk about high end specialty polymers. They can be as cheap as commodity polymers to extremely expensive ones depending upon their area of application. Main classes of polymers which fall under the category of specialty polymers are as follows: Conducting Polymers, Liquid Crystal Polymers, Biodegradable Polymers, Biomedical Polymers, Polymer Composites, Electroluminescent Polymers and more.

3.1 LIQUID CRYSTAL POLYMERS (VECTRAN) 3.1.1 BRIEF INTRODUCTION A polymer that under suitable conditions of temperature, pressure & concentration, exist as liquid crystal is known as liquid crystal polymer and polymers that form liquid crystal stage contain long, rigid units or disc shaped molecular structure called as mesogens. Liquid crystal polymers are sold by manufacturers under variety of trademarks like Kevlar, Vectran and Zenite 5145L. Liquid-crystal polymers (LCPs) are a class of aromatic polyester polymers. LCP (Liquid Crystal Polymers) are of two types based on their preparation process; lyotropic Liquid Crystal Polymers and Thermotropic Liquid Crystal Polymers. In solid form, example of lyotropic LCP is Kevlar and example of Thermotropic LCP is Vectran.

Figure 20 : Molecular Structure of LCP Vectran

3.1.2 PROPERTIES   

LCP’s are extremely unreactive and inert, and highly resistant to fire. Environments that deteriorate the polymers are high-temperature steam, concentrated sulfuric acid, and boiling caustic materials. LCPs have a high mechanical strength at high temperatures, extreme chemical resistance, inherent flame retardancy, and good weatherability.

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3.1.3 APPLICATIONS    

LCPs are useful for electrical and mechanical parts, food containers, and any other applications requiring chemical inertness and high strength. LCP is particularly attractive for microwave frequency electronics due to low relative dielectric constants, low dissipation factors, and commercial availability of laminates. Packaging Micro-electromechanical systems (MEMS) is another area that LCP has recently gained more attention. They are incorporated into various objects to enhance Fire retardant properties.

3.2 ELECTROLUMINESCENT POLYMERS (POLYPHENYLENEVINYLENE (PPV)) 3.2.1 BRIEF INTRODUCTION Electroluminescence is a phenomenon in which a material emits light in response to the passage of an electric current or strong electric field and these are the polymers which emit light in response to the passage of an electric current or strong electric field. Polyphenylene-vinylene (PPV) is the most common example of electroluminescent polymers. PPV (Polyphenylene-vinylene) exhibit electroluminescence. To generate light with these materials, a thin film of semiconducting polymers is sandwiched between two electrodes.

A

A Figure 21 : Molecular Structure of PPV

3.2.2 PROPERTIES   

It is diamagnetic in nature & has a very low thermal conductivity (10 – 13 S/ cm). Tg is 85ºC and Tm is 285ºC. It is water soluble, but its precursors can be manipulated in aqueous solution.

3.2.3 APPLICATIONS

22



It is capable of electroluminescence. Due to its stability, processability & electrical as well as optical properties, PPV is used in organic light emitting diode (OLED). Devices based on PPV an emissive layer, emit bright yellow-green fluorescent light & derivatives of PPV are used when light of different color is required. It is also used as electron donating material in organic solar cells.

 

3.3 GLASS FIBRE REINFORCED POLYMER (GLASS FRP) 3.3.1 BRIEF INTRODUCTION Glass fibers are obtained by forcing glass melt through spinnerets (having small holes) and rapidly pulling & cooling to get fibers. Glass fiber reinforced polymer is a polymer matrix containing nylon, polyesters, etc.

3.3.2 PROPERTIES   

Lower densities. Excellent resistance to corrosion & chemicals. They show applications in limited temperature range as Polymer matrix flows at high temperature. High tensile strength & impact resistance.



3.3.3 APPLICATIONS 

They are used in automobile parts, storage tanks, industrial flooring, plastic pipes, etc. They are extensively used in automobiles to reduce vehicle weight & boost fuel efficiency.



3.4 CARBON FIBRE REINFORCED POLYMER (CARBON FRP) 3.4.1 BRIEF INTRODUCTION Carbon fibers are obtained by pyrolysis of cellulose / Acrylonitrile in an inert atmosphere. It has much higher elasticity modulus than glass fibers & show better resistance to temperature & corrosive chemicals. However, they are short fibers & are more expensive. They use carbon fibers reinforced in polymer matrix like epoxy or polyester resins.

3.4.2 PROPERTIES   

Low density. Resistance to high temperature. Excellent resistance to corrosion.

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3.4.3 APPLICATIONS  

They are used as structural components (like wings, body, stabilizers, etc.) of aircrafts & helicopters. They are used in making sports goods (rackets, archery, racing bicycles, etc.), laptops, fishing rods, musical instruments, etc.

3.5 POLYHYDROXYBUTARATE-HYDROXYVALARATE (PHBV)

3.5.1 BRIEF INTRODUCTION It can be produced by Alcaligenes eutrophus when grown in the presence of glucose & either propanoic or valeric acid. PHBV is a copolymer of 3-hydroxybutanoic acid and 3hydroxypentanoic acid. PHBV may also be synthesized from butyrolactone and valerolactone in the presence of oligomeric aluminoxane as catalyst. IUPAC Name: Poly(3-hydroxybutyrate-co-3-hydroxyvalerate)

O A

O

CH

CH2

C

O O

CH

CH2

C

A n

CH3 CH3 Figure 22: Repeating Unit of PHBV

3.5.2 PROPERTIES   

PHBV is a thermoplastic polymer. It is brittle, has low elongation at break and low impact resistance. Primitive mechanical properties. It is expensive and has low thermal stability.

3.5.3 APPLICATIONS   

PHBV are used for controlled drug delivery as they are biocompatible & biodegradable. Also it is non-toxic. PHBV can be used as a sole structural material or as a part of degradable composites. PHBV can be used for films, blow molded bottles & as a coating on paper.

3.6 POLYCARBONATE (THERMOPLASTIC POLYMER)

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3.6.1 BRIEF INTRODUCTION Polycarbonates (PC), known by the trademarked names Lexan, Makrolon, Makroclear and others, are a particular group of thermoplastic polymers. They are easily worked, molded, and thermoformed. Because of these properties, polycarbonates find many applications. It can be obtained by interaction of Bisphenol-A with diphenyl carbonate.

Figure 23: Preparation of Polycarbonate

3.6.2 PROPERTIES    

Its Tm is 265ºC. It has a good resistance (up to 140ºC) and has thermal stability. High impact strength & tensile strength. It has a tendency to yellow with long term ultraviolet exposure.

3.6.3 APPLICATIONS     

They can be used for making electrical insulators, industrial plugs, sockets, switches, covers of cell phones, laptops, papers, etc. The production of CD, DVD’s, and Blue ray Disc by injection molding of polycarbonate. It is also used for widescreens for motorcycles, golf carts, small planes & helicopters. It can also be used for electronic display for use in mobile and portable device for some LCD screens. It can be laminated to make bullet-proof glass.

3.7 BIODEGRADEABLE POLYMER (POLYHYDROXYVALARATE)

3.7.1 BRIEF INTRODUCTION Biodegradable polymers are a specific type of polymer that breaks down after its intended purpose to result in natural byproducts such as gases (CO2, N2), water, biomass, and

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inorganic salts. These polymers are found both naturally and synthetically made, and largely consist of ester, amide, and ether functional groups.

Figure 24: Biodegradable Plastic

3.7.2 APPLICATIONS 

  

It can be used in food packing, foam for industrial packaging, film rapping, disposable plastic packing material such as single serve cups, disposable food service items, etc. Polymers like Polylactic acids are used in controlled drug delivery because of biocompatibility & biodegradability. Cell transplantation using biodegradable polymers scaffolds offers possibility to create completely natural new tissues & replace organ function. These polymers are used as time release coating for fertilizers & pesticides, making films for moisture & heat retention.

3.8 KEVLAR

3.8.1 BRIEF INTRODUCTION Kevlar (Poly paraphenylene terephthalamide) is a very high strength material that can be spun into ropes or fabric sheets that can be used as such or as an ingredient in composite material components. The polymer has very high strength due to intermolecular hydrogen bond formed between carbonyl group and NH group.

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O A

NH

NH

C

O C

A n

Figure 25: Kevlar

3.8.2 PROPERTIES     

It has outstanding high strength to weight ratio. It is thermally stable (M. P. > 500oC). Crystalline density at 25oC is 1.23 g/cm3. Tg is 47oC and Tm is 220oC. It is very resistance to impact & abrasion damage.

3.8.3 APPLICATIONS    

Kevlar is often combined with carbon fibers & embedded in epoxy resins to form hybrid composite that have the ability to withstand catastrophic impact. It can also be used in light weight boat hulls, high performance race cars. It can be used as cables for mooring lines, offshore drilling platforms, for parachute lines, fishing lines, mountaineering ropes & pulley ropes. It can be used in protective clothing & body armor.

3.9 POLYHYDROXYBUTYRATE (PHB) 3.9.1 BRIEF INTRODUCTION

Polyhydroxybutyrate (PHB) is a polyhydroxyalkanoate (PHA), a polymer belonging to the polyesters class that are of interest as bio-derived and biodegradable plastics. The poly3-hydroxybutyrate (P3HB) form of PHB is probably the most common type of polyhydroxyalkanoate, but other polymers of this class are produced by a variety of organisms: these include poly-4-hydroxybutyrate (P4HB), polyhydroxyvalerate (PHV), polyhydroxyhexanoate (PHH), polyhydroxyoctanoate (PHO) and their copolymers.

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Figure 26: Polyhyroxybutyrate

3.9.2 PROPERTIES   

It has Tg 2ºC and Tm 175°C. Good ultra-violet resistance but poor resistance to acids and bases. Nontoxic.

3.9.3 APPLICATIONS   

PHB can be used for films, blow moulded bottles & as a coating on paper. PHB are used for controlled drug delivery as they are biocompatible & biodegradable. Also it is non-toxic. PHB can be used as a sole structural material or as a part of degradable composites.

3.10 CONDUCTING POLYMER (POLYPYRROLE (PPY)) 3.10.1

BRIEF INTRODUCTION

Polypyrrole (PPy) is a type of organic polymer formed from by polymerization of pyrrole. Polypyrroles are conducting polymers, related members being polythiophene, polyaniline, and polyacetylene.

Figure 27: Molecular Structure of Polypyrrole

3.10.2  

PROPERTIES

They are amorphous, showing only weak diffraction. They are stable in air up to 150 °C.

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

PPy is an insulator.

3.10.3   

APPLICATIONS

PPy and related conductive polymers have two main application in electronic devices and for chemical sensors. PPy is also potential vehicle for drug delivery. The polymer matrix serves as a container for proteins.

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Akatherm.com. (n.d.). Retrieved May 6th, 2014, from Akatherm: http://www.akatherm.com/files/Pressure/Material%20properties%20of%20PE.pdf

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Answers. (n.d.). Retrieved May 5th, 2014, from Answers: http://www.answers.com/topic/engineering-plastic#ixzz30rfplnZF

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Cowie, J. (2001). Polymers: Chemistry and Physics of Modern Materials (2nd Edition ed.). London: Nelson Thrones Ltd.

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k-online. (n.d.). Retrieved May 6th, 2014, from k-online: http://www.konline.de/cipp/md_k/custom/pub/content,oid,42634/lang,2/ticket,g_u_e_s_t/~/Commodity_ Plastics.html

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Mark, J. E. (2007). Physical Properties of Polymers Handbook. London: Springer.

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Mohammad, F. (2007). Specialty Polymers: Materials and Applications. New Delhi: I.K. International Publishing House Pvt. Ltd.

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Nicholson, J. W. (2006). The Chemistry of Polymers. Cambridge: Royal Society of Chemistry.

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Polymerprocessing. (n.d.). Retrieved May 5th, 2014, from Polymerprocessing: http://www.polymerprocessing.com/polymers/index.html

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Sigmaaldrich. (n.d.). Retrieved May 5th, 2014, from Sigmaaldrich: http://www.sigmaaldrich.com/materials-science/material-scienceproducts.html?TablePage=16374854#sthash.uXazoaeP.dpuf

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Slideshare. (n.d.). Retrieved May 5th, 2014, from Slideshare: http://www.slideshare.net/Santachem/speciality-polymers

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Slideshare. (n.d.). Retrieved from Slideshare: http://www.slideshare.net/gaurav2481/conducting-polymers



Srinivas, B. (n.d.). Retrieved May 5th, 2014, from Slideshare: http://www.slideshare.net/GreenChem1/unit-3polymers



Wikipedia. (n.d.). Retrieved May 6th, 2014, from Wikipedia: http://en.wikipedia.org/wiki/



Wisegeek. (n.d.). Retrieved May 5th, 2014, from Wisegeek: http://www.wisegeek.com/what-are-engineering-plastics.htm

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