Elastomers and Rubbers

13 Elastomers and Rubbers An elastomer is a polymer with the property of “elasticity”, generally having notably low Young’s modulus and high yield strain compared with other materials.1 The term is often used interchangeably with the term rubber. Elastomers are amorphous polymers existing above their glass transition temperature, so that considerable segmental motion is possible, so it is expected that they would also be very permeable. At ambient temperatures rubbers are thus relatively soft and deformable. Their primary uses are for seals, adhesives, and molded flexible parts. Elastomers may be thermosets (requiring vulcanization, a form of crosslinking) or thermoplastic, called thermoplastic elastomer or TPE. TPEs have two big advantages over the conventional thermoset (vulcanized) elastomers. Those are ease and speed of processing. Other advantages of TPEs are recyclability of scrap, lower energy costs for processing, and the availability of standard, uniform grades (not generally available in thermosets). TPEs are molded or extruded on standard plasticsprocessing equipment in considerably shorter cycle times than those required for compression or transfer molding of conventional rubbers. They are made by copolymerizing two or more monomers, using either block or graft polymerization techniques. One of the monomers provides the hard, or crystalline, polymer segment that functions as a thermally stable component; the other monomer develops the soft or amorphous segment, which contributes the elastomeric or rubbery characteristic. Physical and chemical properties can be controlled by varying the ratio of the monomers and the length of the hard and soft segments. Block techniques create long-chain molecules that have various or alternating hard and soft segments. Graft polymerization methods involve attaching one polymer chain to another as a branch. The properties that are affected by each phase can be generalized: “Hard phase”dPlastic properties:  Processing temperatures  Continuous use temperature

 Tensile strength  Tear strength  Chemical and fluid resistance  Adhesion to inks, adhesives, and over-molding substrates “Soft phase”dElastomeric properties:  Lower service temperature limits  Hardness  Flexibility  Compression set and tensile set This chapter has data on many thermosets and TPEs. TPEs will be discussed first.

13.1 Thermoplastic Polyurethane Elastomers Urethanes are a reaction product of a diisocyanate and long- and short-chain polyether, polyester, or caprolactone glycols. The polyols and the shortchain diols react with the diisocyanates to form linear polyurethane molecules. This combination of diisocyanate and short-chain diol produces the rigid or hard segment. The polyols form the flexible or soft segment of the final molecule. Figure 13.1 shows the molecular structure in schematic form. The properties of the resin depend on the nature of the raw materials, the reaction conditions, and the ratio of the starting raw materials. The polyols used have a significant influence on certain properties of the thermoplastic polyurethane (TPU). Polyether and polyester polyols are both used to produce many products. The polyester-based TPUs have the following characteristic features:  Good oil/solvent resistance  Good UV resistance

Film Properties of Plastics and Elastomers. DOI: 10.1016/B978-1-4557-2551-9.00013-X Copyright Ó 2012 Elsevier Inc. All rights reserved.

339

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Figure 13.1 Molecular structure of a TPU elastomer.

 Abrasion resistance  Good heat resistance  Mechanical properties The polyether-based TPUs have the following characteristic features:  Fungus resistance  Low-temperature flexibility  Excellent hydrolytic stability  Acid/base resistance In addition to the basic components described above, most resin formulations contain additives to facilitate production and processability. Other additives can also be included such as:  Demolding agents  Flame retardants  Heat/UV stabilizers  Plasticizers The polyether types are slightly more expensive and have better hydrolytic stability and lowtemperature flexibility than the polyester types. Manufacturers and trade names: Lubrizol EstaneÒ TPU, Bayer MaterialScience Texin and Desmopan, and BASF ElastollanÒ (Tables 13.1e13.4). The polyester-based BASF ElastollanÒ 800 series is designed primarily for the extrusion of film and sheet applications, and features excellent transparency and the ability to meet a number of specific

certifications (Table 13.5 and Fig. 13.2). The series also is formulated to succeed in applications that require:  Thermal stability  Abrasion resistance  Toughness  Oil/fuel resistance

13.2 Olefinic Thermoplastic Elastomers Polyolefin thermoplastic elastomer (TPO) materials are defined as compounds (mixtures) of various polyolefin polymers, semicrystalline thermoplastics, and amorphous elastomers. Most TPOs are composed of polypropylene and a copolymer of ethylene and propylene called ethyleneepropylene rubber (EPR).6 A common rubber of this type is called EPDM rubber, which has a small amount of a third monomer, a diene (two carbonecarbon double bonds in it). The diene monomer leaves a small amount of unsaturation in the polymer chain that can be used for sulfur crosslinking. Like most TPEs, TPO products are composed of hard and soft segments. TPO compounds include fillers, reinforcements, lubricants, heat stabilizers, antioxidants, UV stabilizers, colorants, and processing aids. They are characterized by high-impact strength, low density, and good chemical resistance; they are used when durability and reliability are primary concerns. Manufacturers and trade names: Advanced Elastomer Systems SantopreneÒ , LyondelBasell Advanced Polyolefins DexflexÒ .

13: E LASTOMERS AND

Table 13.1 Properties of Lubrizol EstaneÒ Ester Type TPU Film & Sheet Grades2 Units

Hardness shore A

Test Method

54660

58213

ISO 868

76

76

58437

58271

58206

58447

58277

86

86

87

90

93

Specific gravity

g/ cm3

ISO 2781

1.19

1.18

1.18

1.19

1.20

1.19

1.19

Tensile strength at break

MPa

ISO 527

23

25

39

42

46

46

47

Tensile stress at 50% elongation

MPa

ISO 527

1.5

2.7

5.1

5.1

4.6

7.0

8.9

Tensile stress at 100% elongation

MPa

ISO 527

1.9

3.2

5.8

6.0

5.0

8.0

10.0

Tensile stress at 300% elongation

MPa

ISO 527

3.4

4.9

10.6

8.0

9.0

14.5

17.4

Elongation at break

%

ISO 527

840

700

540

650

600

540

550

Tear strength nicked

kN/m

ISO 34-1B

40

45

60

60

70

85

100

ISO 4649-B

25

49

35

70

35

40

55

3

Abrasion resistance

mm

Vicat softening point



C

ISO 306 (A50)

45

45

75

58

75

95

74

Kofler melting point



C

Lubrizol

127

90

165

120

90

170

150

Soft

Elastic

Adhesive

Special features

RUBBERS

Physical Properties

High Heat

341

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Table 13.2 Properties of Lubrizol EstaneÒ Ether Type TPU Film & Sheet Grades2 Physical Properties

Units

Hardness shore A 3

Test Method

58201

58300

58315

58887

ISO 868

82

83

85

88

ISO 2781

1.11

1.10

1.12

1.13

Specific gravity

g/cm

Tensile strength at break

MPa

ISO 527

39

28

37

42

Tensile stress at 50% elongation

MPa

ISO

3.8

4.1

5.0

6.0

Tensile stress at 100% elongation

MPa

ISO

4.6

5.4

6.0

7.0

Tensile stress at 300% elongation

MPa

ISO

7.1

8.3

9.0

11.3

Elongation at break

%

ISO

680

725

650

530

Tear strength nicked

kN/m

ISO 34-1B

45

50

55

65

ISO 4649-B

45

70

35

40

3

Abrasion resistance

mm

Vicat softening point



C

ISO 306 (A50)

60

60

73

79

Kofler melting point



C

Lubrizol

125

140

150

155

UV

UV

UV

Special features

Table 13.3 Permeation of Gases and Vapors through Lubrizol EstaneÒ TPU3

Permeant Gas Air

58315

250

58237

550

Nitrogen

400

Carbon dioxide

102,300

Helium

29,100

Argon

11,200

Freon 12

12,200

FreonÒ 22

10,600

Water

Water Vapor Transmission Rate (g mm/m2 day)

5200 16,200

Permeant Vapor

EstaneÒ Code

Permeability Coefficient (cm3 mm/m2 day atm)

Oxygen

Ò

Table 13.4 Permeation of Water Vapor at 23  C and 50% RH through Lubrizol EstaneÒ TPU4

Vapor Permeation Rate (g mm/m2 day) 0.1

Thickness: 1.14 mm.

Test method: ASTM E-96B.

13.3 Thermoplastic Copolyester Elastomers Thermoplastic copolyester elastomers (TPE-E or COPE) are block copolymers.8 The chemical structure of one such elastomer is shown in Fig. 13.3. These TPEs are generally tougher over a broader temperature range than the urethanes described in Section 13.1. Also, they are easier and more forgiving in processing.  Excellent abrasion resistance

Applications and uses: Roofing and automotive exterior parts, capping distilled water, dairy products, fruit juices, sports drinks, beer, wine, and food, cosmetics, toiletries, and pharmaceutical packaging, sterilized closures, seals, and liners (Tables 13.6 and 13.7).

 High tensile, compressive, and tear strength  Good flexibility over a wide range of temperatures  Good hydrolytic stability  Resistance to solvents and fungus attack  Selection of a wide range of hardness

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Table 13.5 Properties of BASF ElastolanÒ TPU Film Grades5 ElastolanÒ Grad Property

Units

Hardness shore A

Test Method ISO 868

3

SP 806

SP 883

880 AN

890 AN

87

85

78

94

Density

g/cm

Tensile strength

MPa

ISO 37

45

40

40

50

Elongation at break

%

ISO 37

550

550

650

550

Stress at 20% elongation

MPa

ISO 37

2.5

2

2.8

Stress at 100% elongation

MPa

ISO 37

6

5

5.5

10

Stress at 300% elongation

MPa

ISO 37

11.5

10.5

9.5

22.5

Tear strength

kN/mm

ISO 34-1/B/b

60

60

60

120

ISO 4649

30

40

45

45

Abrasion loss

mm

3

ISO 1183-1-A

1.12

1.19

1.21

1.22

5.7

Figure 13.2 Stress vs. strain of BASF ElastolanÒ TPU film.

In these polyester TPEs, the hard polyester segments can crystallize, giving the polymer some of the attributes of semicrystalline thermoplastics, most particularly better solvent resistance than ordinary rubbers, but also better heat resistance. Above the melting temperature of the crystalline regions, these TPEs can have low viscosity and can be molded easily in thin sections and complex structures. Properties of thermoplastic polyester elastomers can be fine-tuned over a range by altering the ratio of hard to soft segments. In DuPont HytrelÒ polyester TPEs, the resin is a block copolymer. The hard phase is polybutylene terephthalate (PBT). The soft segments are longchain polyether glycols. HytrelÒ engineering TPEs

offer a unique combination of strength, elasticity, and flexibility, without the use of plasticizers. By varying resin composition and hardness, appropriate physical properties can be attained as well as a broad range of moisture vapor transmission rates (MVTRs). Very thin monolithic films of 0.001 in. or less can be prepared by extrusion, melt casting (with or without carrier paper) or by blown film processing. HytrelÒ films transmit water vapor via an absorption, diffusion, desorption mechanism. In contrast to microporous structures, HytrelÒ films have no holes that can become clogged. Hence, MVTRs remain high during end-use, and comfort is not compromised. DuPont does not manufacture thin films from HytrelÒ , so data from film are limited.

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Table 13.6 Permeation of Gases at 23  C through Advanced Elastomer Systems SantopreneÒ TPO7

201 e87

203 e50

Permeant Gas

Permeability Coefficient (cm3 mm/m2 day atm)

Air

240

302

140

Nitrogen

194

264

93

Oxygen

504

434

279

Carbon dioxide

3023

2015

1318

519

597

395

1163

3333

1938

Argon Propane

AND

E LASTOMERS

Table 13.7 Water Vapor Transmission at 25  C through Advanced Elastomer Systems SantopreneÒ TPO6

SantopreneÒ Grade 201 e73

P LASTICS

OF

Santoprene Grade

Ò

ASTM E96 Procedure A

ASTM E96 Procedure BW

25% RH

75% RH

Vapor Permeation Rate (g mm/m2 day)

201-73

0.49

0.23

201-87

0.16

0.23

203-50

0.23

0.81

Thickness: 0.5 mm. Test method: ASTM E96.

Thickness: 0.5 mm. Test method: ASTM D1434.

Figure 13.3 Molecular structure of Ticona RiteflexÒ thermoplastic copolyester elastomers.

Table 13.8 Properties of Several DuPontÔ HytrelÒ Thermoplastic Copolyester Elastomer9 HytrelÒ Property

Test Method

Units

4056

5556

6356

Yield stress

ISO 527

MPa

19

Yield strain

ISO 527

%

35

Stress at break

ISO 527

MPa

Strain at break

ISO 527

Nominal strain at break

7246

25

40

43

53

%

400

480

450

450

ISO 527

%

500

600

500

Tensile modulus

ISO 527

MPa

58

180

280

525

Tensile stress at 5% strain

ISO 527

MPa

2.4

12

14

Tensile Stress at 10% strain

ISO 527

MPa

4.5

15

23

Tensile Stress at 50% strain

ISO 527

MPa

8

6.9 11

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345

HytrelÒ films are often bonded to textiles for both disposable and reusable applications. For reusable applications such as outdoor apparel, durability in use and in laundering are important criteria. For these, the HytrelÒ film generally needs to be laminated to one or more fabric layers with either aqueous- or solvent-based adhesives. Typical applications are:  Film/fabric laminates of HytrelÒ are finding increasing acceptance in end-uses requiring waterproof, breathable, and windproof characteristics.  Disposable application of HytrelÒ film include operating room gowns and personal protective apparel. Reusable end-uses include ski, snowboard, and hunting apparel. Included in these are inserts for gloves, either via the conventional cut

Table 13.9 Permeability of Various Gases at 21.5  C through DuPontÔ HytrelÒ 4056 Thermoplastic Copolyester Elastomer10 Permeability Coefficient (cm3 mm/m2 day atm)

Gas

and seam approach or by a revolutionary seamless, three-dimensional route.  The increasing acceptance of HytrelÒ film is resulting in extensions into applications such as backpacks and bedding covers for allergy control. Manufacturers and trade names: Ticona RiteflexÒ , DuPontÔ HytrelÒ , Eastman EcdelÒ , and DSM Engineering plastics ArnitelÒ (Tables 13.8e13.14).  HytrelÒ 4056d40 nominal shore D, containing nondiscoloring stabilizer, low melting, plasticizer free.  HytrelÒ 5556dMedium modulus HytrelÒ grade with nominal durometer hardness of 55D.  HytrelÒ 6356d63 nominal shore D, containing nondiscoloring stabilizer, plasticizer free.

Table 13.10 Permeability of Various Gases at 21.5  C through DuPontÔ HytrelÒ 5556 Thermoplastic Copolyester Elastomer10 Permeability Coefficient (cm3 mm/m2 day atm)

Gas

Air

210

Air

160

Nitrogen

150

Nitrogen

120

Carbon dioxide

3100

Carbon dioxide

Helium

1370

Helium

870

Propane

<18

Propane Water Ò

Freon 12

<18 270,000 120

Ò

Freon 22 Ò

Freon 114

41 3600

Table 13.11 Permeability of Various Gases at 21.5  C through DuPontÔ HytrelÒ 6356 Thermoplastic Copolyester Elastomer10 Permeability Coefficient (cm3 mm/m2 day atm)

Gas

Water

1600

210,000

Ò

105

Ò

52

Ò

2500

Freon 12 Freon 22 Freon 114

Table 13.12 Permeability of Various Gases at 21.5  C through DuPontÔ HytrelÒ 7246 Thermoplastic Copolyester Elastomer10 Permeability Coefficient (cm3 mm/m2 day atm)

Propane

<18

Gas

FreonÒ 12

105

Helium

280

<18

Ò

72

Ò

240

Ò

Freon 22 Ò

Freon 114

400

Freon 12 Freon 114

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Table 13.13 Permeability of Oxygen at 23  C through Ticona RiteflexÒ 663 Thermoplastic Copolyester Elastomer11 Permeability Coefficient (cm3 mm/m2 day atm)

Test Conditions

38  C

Film cast at temperature

93  C

0% RH

37.1

34.2

50% RH

37.1

34.7

100% RH

38.9

35.8

Cast film thickness: 0.035 mm.

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properties by varying the monomeric block types and ratios.  Light weight  Great flexibility (extensive range)  Resiliency  Very good dynamic properties  High strength  Outstanding impact resistance properties at low temperature  Easy processing  Good resistance to most chemicals

Table 13.14 Permeability of Oxygen and Carbon dioxide through Eastman EcdelÒ 9966 Thermoplastic Copolyester Elastomer12

Temperature  C

Permeability Coefficient (cm3 mm/m2 day atm)

Carbon dioxide

23

>1000

Oxygen

30

130

Gas

OF

RH: 50%. Test method: ASTM D1434.

 HytrelÒ 7246dHigh flow, low modulus grade containing at least 50% renewably sourced ingredients by weight.

13.4 Thermoplastic Polyether Block Polyamide Elastomers (PEBA) Polyether block amides are plasticizer-free TPEs.13 The soft segment is the polyether and the hard segment is the polyamide (Nylon). For example, Arkema PEBAXÒ 33 series products are based on Nylon 12 (see Section 8.2) and polytetramethylene glycol segments (PTMG). They are easy to process by injection molding and profile or film extrusion. Often they can be easily meltblended with other polymers, and many compounders will provide custom products by doing this. Their chemistry allows them to achieve a wide range of physical and mechanical

 Breathable films, i.e., impermeable to water whilst permeable to steam  Excellent resistance to hydrolysis  Resistance to perforation Manufacturers and trade names: Arkema PEBAXÒ , EMS-Grivory GrilflexÒ . Applications and uses: Medical. Surgical garments and sheeting; Textile. Sports, leisure, and workwear; Construction. Membranes, housewrap; roofing film; and food and agriculture packaging (Tables 13.15e13.18 and Figs 13.4e13.6). Arkema PEBAXÒ , products most commonly used for film applications:  PEBAXÒ MV1041 hardness 60 shore D, breathable, permanent antistatic grade  PEBAXÒ MV1074 hardness 40 shore D, breathable, permanent antistatic grade  PEBAXÒ MV3000 hardness 35 shore D, specifically designed for medical and food uses  PEBAXÒ MV6100 hardness 58 shore D, specifically designed for medical and food uses

13.5 Styrenic Block Copolymer Thermoplastic Elastomers Styrenic block copolymer (SBC) TPEs are multiphase compositions in which the phases are chemically bonded by block copolymerization (see Chapter 1.2). At least one of the phases is a hard styrenic polymer. This styrenic phase may become

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Table 13.15 Properties of Arkema PEBAXÒ PEBA Films14

Property

MV 1041 SA 01

Units

MV 1074 SA 01

MV 3000 SP 01

MV 3000 SA 01

Test Method

Density

g/cm3

1.04

1.07

1.02

1.04

ISO 1183

Water absorption at equilibrium (20  C, 50% RH)

%

0.9

1.4

1

0.9

ISO 62

Water absorption at equilibrium (23  C, 24 h in water)

%

Melting point



Shore hardness*

12

48

28

11

170

158

158

170

Shore D

60

40

35

58

ISO 868

Tensile stress at break*

MPa

44

30

35

48

ASTM D638

Tensile strain at break*

%

450

>700

500

Flexural modulus

MPa*

270

80

45

*Samples

C

ISO 62

ISO 11357

ASTM D638 210

ISO 178



conditioned 15 days at 23 C and 50% RH.

Table 13.16 Permeability of Oxygen, Carbon dioxide, and Nitrogen at 23  C and 0% RH through Arkema PebaxÒ Films7,15 Permeability Coefficient (cm3 mm/cm2 day atm) Oxygen

Carbon dioxide

Nitrogen

Helium

3533

860

11,800

657

1142

2533

985

17,100

1116

1543

5533

230

3280

72

460

4033

387

5122

256

965

6333

204

2760

33

302

MV3000

463

4425

75

MV6100

163

1800

17

MV1205

600

4375

98

PEBD

150

675

70

PEBAX Product Code

fluid when the TPE composition is heated. Another phase is a softer elastomeric material that is rubberlike at room temperature. The polystyrene blocks act as crosslinks, tying the elastomeric chains together in a three-dimensional network. SBC TPEs have no commercial applications when the product is just a pure polymer. They must be compounded with other polymers, oils, fillers, and additives to have any commercial value.

Propane

789 236

Manufacturers and trade names: BASF StyroluxÒ . Applications and uses: Primarily food packaging, packed fruit and vegetables, fresh pasta and cheese, as thermoformed cups and lids, and also in applications including shrink film, must stay fresh as long as possible. Styrolux co-extruded with other thermoplastics, provides transparent barrier-layer composites (Table 13.19).

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Table 13.17 Water Vapor Permeation at 38  C and 50% RH through Arkema PebaxÒ Films16 At 50% RH Vapor Transmission Rate (g mm/m2 day)

PEBAX Thickness (mm)

0.012

0.012

0.025

At 90% RH Vapor Transmission Rate (g mm/m2 day) 0.050

0.025

0.050

MX1205

36

36

45

36

45

70

MV1041

216

216

300

42

68

90

MV3000

336

336

550

54

82

110

MV1074

360

360

625

57

107

180

MV6100

150

Test method: ASTM E96 E.

Table 13.18 Water Vapor Permeability at 38  C and 100% RH through Arkema PebaxÒ films6 PEBAX

Vapor Transmission Rate (g mm/m2 day)

6333

31

5533

34

4033

38

3533

67

2533

89

Figure 13.4 Stress vs. strain at various temperatures of Arkema PEBAXÒ MV1041SA 01 PEBA film.

13.6 Syndiotactic 1,2Polybutadiene Syndiotactic 1,2-polybutadiene is made from butadiene as shown in Fig. 13.7. The isomeric structure is syndiotactic as described in Chapter 1.7.3. Manufacturers and trade names: Japanese Synthetic Rubber Company is the only known manufacturer, JSR RB. Film processing: Blown film and cast film. Film applications: Films for industrial uses, melting bags (Table 13.20 and Figs 13.8e13.11).

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349

Figure 13.5 Stress vs. strain at various temperatures of Arkema PEBAXÒ MV1041SA 01 PEBA film.

Figure 13.6 Water vapor permeation vs. film thickness at 38  C and 50% relative humidity (RH) through Arkema PEBAXÒ breathable PEBA films per ASTM E96.19

Table 13.19 Permeability of Oxygen, Nitrogen, and Carbon dioxide at 23  C Through BASF StyroluxÒ Films17 Oxygen Permeability Coefficient (cm3 mm/cm2 day atm)

Nitrogen Permeability Coefficient (cm3 mm/cm2 day atm)

Carbon dioxide Permeability Coefficient (cm3 mm/cm2 day atm)

684 D

263

70.9

1520

656 C

162

35.5

811

StyroluxÒ

Thickness: 0.1 mm.

350

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Figure 13.7 Reaction producing 1,2-polybutadiene.

Table 13.20 Properties of JSR Syndiotactic 1,2-Polybutadiene Film Resins18 Property

Test Method

Units

Density

ASTM D1505

g/cm

3

Percentage 1,2 bonds

IR

%

Tensile strength at break

ASTM D412

MPa

Elongation at break

ASTM D412

%

Hardness shore D

JSR RB810 0.901 90 6.4

JSR RB820 0.906

JSR RB830 0.909

92

93

10.3

12.7

750

700

670

ASTM D2240

32

40

47

Hardness shore A

ASTM D2240

82

95

99

Transmittance

ASTM D1003

%

91

89

82

Haze

ASTM D1003

%

2.6

3.4

8.0

Figure 13.8 Stress vs. strain behavior of several Japanese Synthetic Rubber Company syndiotactic 1,2-polybutadiene films.18

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351

Figure 13.9 Stress vs. strain at different temperatures of Japanese Synthetic Rubber Company RB820 syndiotactic 1,2-polybutadiene films.18

Figure 13.10 Tensile strength vs. filler content of Japanese Synthetic Rubber Company RB820 syndiotactic 1,2-polybutadiene films.18

References 1. McKeen LW. The effect of temperature and other factors on plastics, plastics design library. William Andrew Publishing; 2008. 2. EstaneÒ TPU film & sheet grades. Lubrizol; 2010. 3. Estane thermoplastic polyurethane for film and sheet applications, E-30. Noveon Inc; 2001.

Figure 13.11 Elongation of break vs. filler content of Japanese Synthetic Rubber Company RB820 syndiotactic 1,2-polybutadiene films.18

4. Estane breathable-high moisture vapor transmission selection guide. Lubrizol; 2007. 5. ElastolanÒ product range. BASF; 2005. 6. Drobny JG. Handbook of thermoplastic elastomers. William Andrew; 2007. p. 191e99. 7. SantopreneÒ rubber physical properties guide, advanced elastomer systems; 2005. 8. Drobny JG. Handbook of thermoplastic elastomers. William Andrew; 2007. p. 249e64.

352

9. Product information sheets. DuPontÔ; 2005. 10. HytrelÒ design guide-module V, H-81098. DuPontÔ; 2000. 11. RiteflexÒ brochure RF-001. Ticona; 2006. 12. Ecdel products and packaging for the medical industry, PPM-201B. Eastman; 1999. 13. Drobny JG. Handbook of thermoplastic elastomers. William Andrew; 2007. p. 235e47. 14. Technical data sheets. Arkema; 2009.

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15. PebaxÒ application areas. Arkema; 2004. 16. PebaxÒ , supplier design guide. Atochem; 1987. 17. Styrolux product line, properties, processing, supplier design guide [B 583e/(950) 12.91]. BASF Aktiengesellschaft; 1992. 18. On JSR RB. Japanese Synthetic Rubber Company; 2004. 19. PebaxÒ breathable film. Arkema; 2009.