Polyesters

4 Polyesters Polyesters are formed by a condensation reaction that is very similar to the reaction used to make polyamide or nylons. A diacid and dialcohol are reacted to form the polyester with the elimination of water as shown in Figure 4.1. While the actual commercial route to making the polyesters may be more involved, the end result is the same polymeric structure. The diacid is usually aromatic. Polyester resins can be formulated to be brittle and hard, tough and resilient, or soft and flexible. In combination with reinforcements such as glass fibers, they offer outstanding strength, a high strength-to-weight ratio, chemical resistance, and other excellent mechanical properties. The three dominant materials in this plastics family are polycarbonate (PC), polyethylene terephthalate (PET), and polybutylene terephthalate (PBT). Thermoplastic polyesters are similar in properties to Nylon 6 and Nylon 66 but have lower water absorption and higher dimensional stability than the nylons.

4.1 Polycarbonate Theoretically, PC is formed from the reaction of bisphenol A and carbonic acid. The structures of these two monomers are given in Figure 4.2. Commercially, different routes are used, but the PC polymer of the structure shown in Figure 4.3 is the result. PC performance properties include:

• High impact resistance and it is virtually unbreakable and temperatures

• • • •

remains

tough

at

low

“Clear as glass” clarity High heat resistance Dimensional stability Resistant to ultraviolet light, allowing exterior use

• Flame-retardant properties.

Figure 4.1 Condensation polymerization reaction produces polyesters.

Figure 4.2 Chemical structures of monomers used to make PC polyester.

Figure 4.3 Chemical structure of PC polyester.

McKeen: The Effect of Creep and other Time Related Factors on Plastics and Elastomers. DOI: http://dx.doi.org/10.1016/B978-0-323-35313-7.00004-3 © 2015 Elsevier Inc. All rights reserved.

141

142

THE EFFECT

OF

CREEP

AND OTHER

TIME RELATED FACTORS

ON

PLASTICS

AND

ELASTOMERS

Figure 4.4 Chemical structure of isophorone bisphenol (trimethyl cyclohexyl bisphenol).

Table 4.1 The Deformation Under Compressive Load at Various Temperatures of Mitsubishi Engineering-Plastics Corp Novarex® and Iupilon® PC [2]

Load (MPa)

ASTM D621-51 Deformation After 24 h (%)

25

27.5

0.220

70

27.5

0.282

25

13.7

0.101

70

13.7

0.080

Temperature (°C)

Table 4.2 The Tensile Deformation and Recovery of Mitsubishi Engineering-Plastics Corp Novarex® and Iupilon® PC at 100° [2] Stress (MPa)

Initial Strain (%)

Creep After 1000 h (%)

Total Deformation (%)

Recovery Rate (Recovery/ Total Deformation) (%)

3.84

0.0298

0.2797

0.3095

38.5

7.70

0.3059

0.6941

1.000

32.2

15.4

0.7267

1.300

2.027

35.3

19.2

1.162

3.500

4.662

21.0

Other bisphenols are often used in place of bisphenol A. Isophorone bisphenol is common and its structure is shown in Figure 4.4. Copolymer PCs are also common where blends of different bisphenols are used. These are often block copolymers. The Tg of the copolycarbonates can be adjusted by changing bisphenol monomers and their ratios. PC sheet and injection molded parts may have a variety of coatings, including a range of hardcoats that enhance weathering, scratch, and abrasion resistance. PC is often blended with other polymers especially ABS, PET, and PBT.

Manufacturers and trade names: Bayer MaterialScience Apec® and Makrolon®, Styron Calibret, Mitsubishi Engineering-Plastics Corporation Iupilon® and Novarex®, SABIC Innovative Plastics Lexan®. Applications and end uses: automotive headlamp lens and reflectors, architectural glazing, safety shields, lenses, casings and housings, light fittings, kitchenware pitchers, glasses and trays, medical apparatus (sterilizable) and CDs and DVDs (the discs), water bottles. Data for PC plastics are found in Tables 4.1 and 4.2 and Figures 4.5 4.21.

4: POLYESTERS

143

4.1.1 SABIC Innovative Plastics Lexan® 101 PC Resins

Figure 4.5 Creep strain versus time at 45°C of SABIC Innovative Plastics Lexan® 101—general purpose PC resin.

Figure 4.6 Creep strain versus time at 23°C of SABIC Innovative Plastics Lexan® 141R—medium viscosity, release PC resin [1].

144

THE EFFECT

OF

CREEP

AND OTHER

TIME RELATED FACTORS

ON

PLASTICS

AND

ELASTOMERS

Figure 4.7 Creep strain versus time at various temperatures and a stress of 15 MPa of SABIC Innovative Plastics Lexan® 141R—medium viscosity, release PC resin [1].

Figure 4.8 Creep strain versus time at 23°C of SABIC Innovative Plastics Thermocomp DF006, PC, 30% glass flake PC resin.

4: POLYESTERS

Figure 4.9 Creep strain versus time at 70°C of SABIC Innovative Plastics Thermocomp DF006, PC, 30% glass flake PC resin.

Figure 4.10 Creep strain versus time at 23°C of SABIC Innovative Plastics Lubricomp DFL36, 30% glass flake, 15% PTFE PC resin.

145

146

THE EFFECT

OF

CREEP

AND OTHER

TIME RELATED FACTORS

ON

PLASTICS

AND

ELASTOMERS

Figure 4.11 Creep strain versus time at 70°C of SABIC Innovative Plastics Lubricomp DFL36, 30% glass flake, 15% PTFE PC resin.

Figure 4.12 Creep strain versus time at 120°C of SABIC Innovative Plastics Lubricomp DFL36, 30% glass flake, 15% PTFE PC resin.

4: POLYESTERS

4.1.2 Mitsubishi Engineering-Plastics Corp Novarex® and Iupilon® PC Resins

Figure 4.13 Tensile creep versus time at 25°C and various stress levels of Mitsubishi Engineering-Plastics Corp Novarex® and Iupilon® PC resin [2].

Figure 4.14 Tensile creep versus time at 75°C and various stress levels of Mitsubishi Engineering-Plastics Corp Novarex® and Iupilon® PC resin [2].

147

148

THE EFFECT

OF

CREEP

AND OTHER

TIME RELATED FACTORS

ON

PLASTICS

AND

ELASTOMERS

Figure 4.15 Tensile creep versus time at 100°C and various stress levels of Mitsubishi Engineering-Plastics Corp Novarex® and Iupilon® PC resin [2].

Figure 4.16 Tensile creep versus time at 125°C and various stress levels of Mitsubishi Engineering-Plastics Corp Novarex® and Iupilon® PC resin [2].

4: POLYESTERS

Figure 4.17 Tensile creep strain versus time at 22°C and a wide range of stress levels of Mitsubishi Engineering-Plastics Corp Novarex® and Iupilon® PC resin [2].

Figure 4.18 Tensile creep stress versus time at 22°C and a wide range of stress levels of Mitsubishi Engineering-Plastics Corp Novarex® and Iupilon® PC resin [2].

149

150

THE EFFECT

OF

CREEP

AND OTHER

TIME RELATED FACTORS

ON

PLASTICS

AND

ELASTOMERS

Figure 4.19 Flexural and compressive creep versus time at various stress levels of Mitsubishi EngineeringPlastics Corp Novarex® and Iupilon® PC resin [2].

Figure 4.20 The tensile deformation at normal temperature and recovery in case load was removed after 1000 h of Mitsubishi Engineering-Plastics Corp Novarex® and Iupilon® PC [2].

4: POLYESTERS

151

Figure 4.21 Relaxation of tensile stress of Mitsubishi Engineering-Plastics Corp Novarex® and Iupilon® PC [2]. Note: Initial load 9.8 MPa, however, 4.9 MPa in case of temperature of 120°C and 130°C.

Figure 4.22 Chemical structure of PBT polyester.

4.2 Polybutylene Terephthalate PBT is a semicrystalline, white or off-white polyester similar in both composition and properties to PET. It has somewhat lower strength and stiffness than PET, is a little softer but has higher impact strength and similar chemical resistance. As it crystallizes more rapidly than PET, it tends to be preferred for industrial scale molding. Its structure is shown in Figure 4.22. PBT performance properties include:

• High mechanical properties • High thermal properties • Good electrical properties

• Dimensional stability • Excellent chemical resistance • Flame retardancy. Manufacturers and trade names: BASF Ultradur®, DuPont Crastin®, PolyOne Burgadurt, SABIC Innovative Plastics Enduran, Celanese Celanex®, Degussa Vestodur®, Mitsubishi Engineering-Plastics Corporation Novaduran®. Applications and uses: packaging, automotive, electrical, and consumer markets. Data for PBT plastics are found in Figures 4.23 4.88.

152

THE EFFECT

OF

CREEP

AND OTHER

TIME RELATED FACTORS

ON

PLASTICS

AND

ELASTOMERS

Figure 4.23 Isochronous stress strain curves at 23°C of Celanese Celanex® 2500—general purpose, nucleated, easy flow PBT resin [3].

Figure 4.24 Flexural creep at 13.8 MPa maximum stress for 15% glass fiber reinforced PBT resin [4].

4: POLYESTERS

Figure 4.25 Flexural creep versus time curves at 3.4 MPa maximum stress at various temperatures of Celanese Celanex® 3210—18% glass fiber reinforced, flame retardant PBT resin [5].

Figure 4.26 Flexural creep versus time curves at 13.8 MPa maximum stress at various temperatures of Celanese Celanex® 3210—18% glass fiber reinforced, flame retardant PBT resin [5].

153

154

THE EFFECT

OF

CREEP

AND OTHER

TIME RELATED FACTORS

ON

PLASTICS

AND

ELASTOMERS

Figure 4.27 Isochronous stress strain curves at 23°C of Celanese Celanex® 2300 GV/30—general purpose, 30% glass fiber reinforced PBT resin [3].

Figure 4.28 Flexural creep versus time curves at 3.4 MPa maximum stress at various temperatures of Celanese Celanex® 3300—30% glass fiber reinforced, general purpose PBT resin [4].

4: POLYESTERS

Figure 4.29 Flexural creep versus time curves at 14 MPa maximum stress at various temperatures of Celanese Celanex® 3300—30% glass fiber reinforced, general purpose PBT [4].

Figure 4.30 Flexural creep at 105°C for glass reinforced Celanese Celanex® 3300—30% glass fiber reinforced, general purpose PBT resin [4].

155

156

THE EFFECT

OF

CREEP

AND OTHER

4.2.1 Celanese Celanex® PBT Resins In Figures 4.31 4.35, data on the following products are presented:

• Celanese Celanex® 2360 GV/10/30 FL—30% glass fiber reinforced, flame retardant

• Celanese Celanex® 2300 GV/10—general purpose, 10% glass fiber reinforced

• Celanese Celanex® 2300 GV/20—general pur-

TIME RELATED FACTORS

ON

PLASTICS

AND

ELASTOMERS

• Celanese Celanex® 2300 GV/30—general purpose, 30% glass fiber reinforced

• Celanese Celanex® 2300 GV/40—general purpose, 40% glass fiber reinforced

• Celanese Celanex® 2500—general purpose, nucleated, easy flow

• Celanese Celanex® 3300—general purpose, 30% glass fiber reinforced

• Celanese Celanex® 3310—30% glass fiber reinforced, flame retardant.

pose, 20% glass fiber reinforced

Figure 4.31 Creep strain versus time comparison of Celanese Celanex® 3300 and Celanex® 3310 PBT resins at a stress of 13.8 MPa showing the effect of a fire-resistant additive [5].

Figure 4.32 Flexural creep modulus versus time comparison at 23°C and a stress of 10 MPa of Celanese Celanex® PBT resins with different levels of glass fiber reinforcement [3].

4: POLYESTERS

157

Figure 4.33 Flexural creep modulus versus time comparison at 80°C and a stress of 5 MPa of Celanese Celanex® PBT resins with different levels of glass fiber reinforcement [3].

Figure 4.34 Tensile creep modulus of different Celanese Celanex® grades, measured in the tensile creep test (ISO 899), test temperature 23°C, stress a 5 40 MPa, b 5 35 MPa, c 5 7 MPa [3].

158

THE EFFECT

OF

CREEP

AND OTHER

TIME RELATED FACTORS

ON

PLASTICS

AND

ELASTOMERS

Figure 4.35 Tensile creep curves for different Celanese Celanex® grades, measured in the tensile creep test (ISO 899), test temperature 23°C, stress a 5 40 MPa, b 5 35 MPa, c 5 7 MPa [3].

4.2.2 DuPont Engineering Polymers Crastin® PBT Resins

Figure 4.36 Isochronous stress strain curves at 23°C of DuPont Engineering Polymers Crastin® S600F10 NC010—medium viscosity, lubricated PBT resin.

Figure 4.37 Isochronous stress strain curves at 60°C of DuPont Engineering Polymers Crastin® S600F10 NC010—medium viscosity, lubricated PBT resin.

4: POLYESTERS

159

Figure 4.38 Isochronous stress strain at 23°C of DuPont Engineering Polymers Crastin® ST820 NC010—super tough, lubricated PBT resin.

Figure 4.40 Isochronous stress strain curves at 60°C of DuPont Engineering Polymers Crastin® SK601—10% glass flake reinforced, lubricated PBT resin.

Figure 4.39 Isochronous stress strain curves at 23°C of DuPont Engineering Polymers Crastin® SK601—10% glass flake reinforced, lubricated PBT resin.

Figure 4.41 Isochronous stress strain curves at 23°C of 9 DuPont Engineering Polymers Crastin® SK603—20% glass flake reinforced, lubricated PBT resin.

160

THE EFFECT

OF

CREEP

AND OTHER

Figure 4.42 Isochronous stress strain curves at 23°C of DuPont Engineering Polymers Crastin® SK605—30% glass flake reinforced, lubricated PBT resin.

Figure 4.43 Isochronous stress strain at 23°C of DuPont Engineering Polymers Crastin® T805—30% glass flake reinforced, toughened PBT resin.

TIME RELATED FACTORS

ON

PLASTICS

AND

ELASTOMERS

Figure 4.44 Isochronous stress strain of at 80°C of DuPont Engineering Polymers Crastin® T805— 30% glass flake reinforced, toughened PBT resin.

Figure 4.45 Isochronous stress strain curves at 23°C of DuPont Engineering Polymers Crastin® SK609—50% glass flake reinforced, lubricated PBT resin.

4: POLYESTERS

161

Figure 4.46 Isochronous stress strain curves at 60°C of DuPont Engineering Polymers Crastin® SK609—50% glass flake reinforced, lubricated PBT resin.

Figure 4.48 Isochronous stress strain at 60°C of DuPont Engineering Polymers Crastin® T841FR— 10% glass flake reinforced, toughened, fire-resistant PBT resin.

Figure 4.47 Isochronous stress strain of at 23°C of DuPont Engineering Polymers Crastin® T841FR—10% glass flake reinforced, toughened, fire-resistant PBT resin.

Figure 4.49 Isochronous stress strain of at 23°C of DuPont Engineering Polymers Crastin® T843FR—20% glass flake reinforced, toughened, fire-resistant PBT resin.

162

THE EFFECT

OF

CREEP

AND OTHER

Figure 4.50 Isochronous stress strain at 60°C of DuPont Engineering Polymers Crastin® T843FR— 20% glass flake reinforced, toughened, fire-resistant PBT resin.

TIME RELATED FACTORS

ON

PLASTICS

AND

ELASTOMERS

Figure 4.51 Isochronous stress strain at 23°C of DuPont Engineering Polymers Crastin® T845FR— 30% glass flake reinforced, toughened, fire-resistant PBT resin.

Figure 4.52 Isochronous stress strain at 60°C of DuPont Engineering Polymers Crastin® T845FR—30% glass flake reinforced, toughened, fire-resistant PBT resin.

4: POLYESTERS

163

4.2.3 Evonik Industries Vestodur® PBT Resins

Figure 4.53 Tensile creep strain versus time at 23°C and 50% relative humidity of Evonik Industries Vestodur® 2000—unreinforced, medium viscosity PBT resin [6].

Figure 4.54 Tensile creep strain versus time at 100°C of Evonik Industries Vestodur® 2000—unreinforced, medium viscosity PBT resin [6].

164

THE EFFECT

OF

CREEP

AND OTHER

TIME RELATED FACTORS

ON

PLASTICS

AND

ELASTOMERS

Figure 4.55 Tensile creep modulus curves at 23°C and 50% relative humidity of Evonik Industries Vestodur® 2000—unreinforced, medium viscosity PBT resin [6].

Figure 4.56 Tensile creep modulus curves at 100°C of Evonik Industries Vestodur® 2000—unreinforced, medium viscosity PBT resin [6].

4: POLYESTERS

165

Figure 4.57 Tensile creep strain versus time at 23°C and 50% relative humidity of Evonik Industries Vestodur® HI19—unreinforced, stabilized, with mold release agent PBT resin [6].

Figure 4.58 Tensile creep strain versus time at 100°C of Evonik Industries Vestodur® HI19—unreinforced, stabilized, with mold release agent PBT resin [6].

166

THE EFFECT

OF

CREEP

AND OTHER

TIME RELATED FACTORS

ON

PLASTICS

AND

ELASTOMERS

Figure 4.59 Tensile creep modulus at 23°C and 50% relative humidity of Evonik Industries Vestodur® HI19— unreinforced, stabilized, with mold release agent PBT resin [6].

Figure 4.60 Tensile creep modulus at 100°C of Evonik Industries Vestodur® HI19—unreinforced, stabilized, with mold release agent PBT resin [6].

4: POLYESTERS

167

Figure 4.61 Tensile creep strain versus time at 23°C and 50% relative humidity of Evonik Industries Vestodur® GF30—30% chopped glass fibers PBT resin [6].

Figure 4.62 Tensile creep strain versus time at 100°C of Evonik Industries Vestodur® GF30—30% chopped glass fibers PBT resin [6].

168

THE EFFECT

OF

CREEP

AND OTHER

TIME RELATED FACTORS

ON

PLASTICS

AND

ELASTOMERS

Figure 4.63 Tensile creep modulus at 23°C and 50% relative humidity of Evonik Industries Vestodur® GF30—30% chopped glass fibers PBT resin [6].

Figure 4.64 Tensile creep modulus at 100°C of Evonik Industries Vestodur® GF30—30% chopped glass fibers PBT resin [6].

4: POLYESTERS

169

Figure 4.65 Tensile creep strain versus time at 23°C and 50% relative humidity of Evonik Industries Vestodur® HI19-GF30—30% glass fiber reinforced terephthalate (PBT) resin [6].

Figure 4.66 Tensile creep strain versus time at 100°C of Evonik Industries Vestodur® HI19-GF30—30% glass fiber reinforced terephthalate (PBT) resin [6].

170

THE EFFECT

OF

CREEP

AND OTHER

TIME RELATED FACTORS

ON

PLASTICS

AND

ELASTOMERS

Figure 4.67 Tensile creep modulus versus time at 23°C and 50% relative humidity of Evonik Industries Vestodur® HI19-GF30—30% glass fiber reinforced terephthalate (PBT) resin [6].

Figure 4.68 Tensile creep modulus versus time at 100°C of Evonik Industries Vestodur® HI19-GF30—30% glass fiber reinforced terephthalate (PBT) resin [6].

4: POLYESTERS

171

4.2.4 BASF Ultradur® PBT Resins

Figure 4.71 Isochronous stress strain at 100°C of BASF Ultradur® B4520—medium viscosity, rapid freezing PBT resin [7]. Figure 4.69 Isochronous stress strain at 23°C and 50% relative humidity of BASF Ultradur® B4520— medium viscosity, rapid freezing PBT resin [7].

Figure 4.70 Isochronous stress 0 at 60°C of BASF Ultradur® B4520—medium viscosity, rapid freezing PBT resin [7].

Figure 4.72 Isochronous stress strain at 23°C and 50% relative humidity of BASF Ultradur® B4300 G6—standard grade, 30% glass fiber reinforced PBT resin [7].

172

THE EFFECT

OF

CREEP

AND OTHER

Figure 4.73 Isochronous stress strain at 60°C and 6% relative humidity of BASF Ultradur® B4300 G6— standard grade, 30% glass fiber reinforced PBT resin [7].

TIME RELATED FACTORS

ON

PLASTICS

AND

ELASTOMERS

Figure 4.74 Isochronous stress strain at 100°C of BASF Ultradur® B4300 G6—standard grade, 30% glass fiber reinforced PBT resin [7].

Figure 4.75 Isochronous stress at 140°C of BASF Ultradur® B4300 G6—standard grade, 30% glass fiber reinforced PBT resin [7].

4: POLYESTERS

173

4.2.5 Mitsubishi Engineering-Plastics Corporation Novaduran® PBT Resins

Figure 4.76 Flexural creep strain versus time at 23°C at various levels of stress of Mitsubishi EngineeringPlastics Corporation Novaduran® 5010R5 unreinforced PBT resin [8].

Figure 4.77 Flexural creep strain versus time at high temperatures and at various levels of stress of Mitsubishi Engineering-Plastics Corporation Novaduran® 5010R5 unreinforced PBT resin [8].

174

THE EFFECT

OF

CREEP

AND OTHER

TIME RELATED FACTORS

ON

PLASTICS

AND

ELASTOMERS

Figure 4.78 Flexural creep modulus versus time at various temperatures and 7 MPa stress of Mitsubishi Engineering-Plastics Corporation Novaduran® 5010R5 unreinforced PBT resin [8].

Figure 4.79 Flexural creep facture stress versus time at various temperatures of Mitsubishi EngineeringPlastics Corporation Novaduran® 5010R5 unreinforced PBT resin [8].

4: POLYESTERS

175

Figure 4.80 Stress relaxation versus time at 23°C at various levels of initial stress of Mitsubishi EngineeringPlastics Corporation Novaduran® 5010R5 unreinforced PBT resin [8].

Figure 4.81 Flexural creep strain versus time at 23°C at various levels of stress of Mitsubishi EngineeringPlastics Corporation Novaduran® 5010G30 30% glass fiber reinforced PBT resin [8].

176

THE EFFECT

OF

CREEP

AND OTHER

TIME RELATED FACTORS

ON

PLASTICS

AND

ELASTOMERS

Figure 4.82 Flexural creep strain versus time at 80°C at various levels of stress of Mitsubishi EngineeringPlastics Corporation Novaduran® 5010G30 30% glass fiber reinforced PBT resin [8].

Figure 4.83 Flexural creep strain versus time at 120°C at various levels of stress of Mitsubishi EngineeringPlastics Corporation Novaduran® 5010G30 30% glass fiber reinforced PBT resin [8].

4: POLYESTERS

177

Figure 4.84 Flexural creep strain versus time at 150°C at various levels of stress of Mitsubishi EngineeringPlastics Corporation Novaduran® 5010G30 30% glass fiber reinforced PBT resin [8].

Figure 4.85 Flexural creep modulus versus time at various temperatures and 7 MPa stress of Mitsubishi Engineering-Plastics Corporation Novaduran® 5010G30 30% glass fiber reinforced PBT resin [8].

178

THE EFFECT

OF

CREEP

AND OTHER

TIME RELATED FACTORS

ON

PLASTICS

AND

ELASTOMERS

Figure 4.86 Flexural creep facture stress versus time at various temperatures of Mitsubishi EngineeringPlastics Corporation Novaduran® 5010G30 30% glass fiber reinforced PBT resin [8].

Figure 4.87 Stress relaxation versus time at 23°C at various levels of initial stress of Mitsubishi EngineeringPlastics Corporation Novaduran® 5010G30 30% glass fiber reinforced PBT resin [8].

4: POLYESTERS

179

Figure 4.88 Comparison of different levels of glass fiber reinforcement on the flexural creep strain versus time of Mitsubishi Engineering-Plastics Corporation Novaduran® PBT resins [8].

Figure 4.89 Chemical structure of PET polyester.

4.3 Polyethylene Terephthalate PET polyester is the most common thermoplastic polyester and is often called just “polyester.” This often causes confusion with the other polyesters in this chapter. PET exists both as an amorphous (transparent) and as a semicrystalline (opaque and white) thermoplastic material. The semicrystalline PET has good strength, ductility, stiffness, and hardness. The amorphous PET has better ductility but less stiffness and hardness. It

absorbs very little water. Its structure is shown in Figure 4.89. Manufacturers and trade names: DuPont Rynite®, DuPont Teijin Filmst Mylar® and Melinex®, Mitsubishi Polyester Film Hostaphan®, Celanese Impet®. Applications and uses: bottles for soft drinks and water, food trays for oven use, roasting bags, audio/video tapes, mechanical components. Data for PET plastics are found in Figures 4.90 4.122.

180

THE EFFECT

OF

CREEP

AND OTHER

TIME RELATED FACTORS

ON

PLASTICS

AND

ELASTOMERS

4.3.1 Celanese Impet® PET Resins

Figure 4.90 Creep modulus versus time at a stress of 13.8 MPa of Celanese Impet® 610R—13% glass fiber/ mineral reinforced, recycled PET resin.

Figure 4.91 Flexural creep modulus versus time at a stress of 27.6 MPa of Celanese Impet® 330R—30% glass reinforced, recycled PET resin [4].

4: POLYESTERS

4.3.2 DuPont Engineering Polymers Rynite® PET Resins

Figure 4.92 Flexural creep versus time at a stress of 27.6 MPa of DuPont Engineering Polymers Rynite® 415HP—toughened, 15% glass fiber reinforced PET resin [9].

Figure 4.93 Flexural creep modulus versus time at a stress of 27.6 MPa of DuPont Engineering Polymers Rynite® 415HP—toughened, 15% glass fiber reinforced PET resin [10].

181

182

THE EFFECT

OF

CREEP

AND OTHER

TIME RELATED FACTORS

ON

PLASTICS

AND

ELASTOMERS

Figure 4.94 Flexural creep versus time at a stress of 27.6 MPa of DuPont Engineering Polymers Rynite® FR515—flame retardant, 15% glass reinforced, higher heat PET resin [9].

Figure 4.95 Flexural creep modulus versus time at a stress of 27.6 MPa of DuPont Engineering Polymers Rynite® FR515—flame retardant, 15% glass reinforced, higher heat PET resin [10].

4: POLYESTERS

Figure 4.96 Isochronous stress strain at 23°C of DuPont Engineering Polymers Rynite® 530—general purpose, 30% glass fiber reinforced PET resin.

Figure 4.97 Flexural creep versus time at a stress of 27.6 MPa of DuPont Engineering Polymers Rynite® 530—general purpose, 30% glass fiber reinforced PET resin [9].

183

184

THE EFFECT

OF

CREEP

AND OTHER

TIME RELATED FACTORS

ON

PLASTICS

AND

ELASTOMERS

Figure 4.98 Flexural creep modulus versus time at a stress of 27.6 MPa of DuPont Engineering Polymers Rynite® 530—general purpose, 30% glass fiber reinforced PET resin [10].

Figure 4.99 Flexural creep versus time at a stress of 27.6 MPa of DuPont Engineering Polymers Rynite® FR530—flame retardant, 30% glass fiber reinforced PET resin [9].

4: POLYESTERS

Figure 4.100 Flexural creep modulus versus time at a stress of 27.6 MPa of DuPont Engineering Polymers Rynite® FR530—flame retardant, 30% glass fiber reinforced PET resin [10].

Figure 4.101 Flexural creep strain versus time at a stress of 6.9 MPa of DuPont Engineering Polymers Rynite® 935—low warp, 35% mica/glass reinforced PET resin [9].

185

186

THE EFFECT

OF

CREEP

AND OTHER

TIME RELATED FACTORS

ON

PLASTICS

AND

ELASTOMERS

Figure 4.102 Flexural creep modulus versus time at a stress of 6.9 MPa of DuPont Engineering Polymers Rynite® 935—low warp, 35% mica/glass reinforced PET resin [10].

Figure 4.103 Flexural creep strain versus time at a stress of 13.8 MPa of DuPont Engineering Polymers Rynite® 935—low warp, 35% mica/glass reinforced PET resin [9].

4: POLYESTERS

Figure 4.104 Flexural creep modulus versus time at a stress of 13.8 MPa of DuPont Engineering Polymers Rynite® 935—low warp, 35% mica/glass reinforced PET resin [10].

Figure 4.105 Flexural creep strain versus time at a stress of 27.6 MPa of DuPont Engineering Polymers Rynite® 935—low warp, 35% mica/glass reinforced PET resin [9].

187

188

THE EFFECT

OF

CREEP

AND OTHER

TIME RELATED FACTORS

ON

PLASTICS

AND

ELASTOMERS

Figure 4.106 Flexural creep modulus versus time at a stress of 27.6 MPa of DuPont Engineering Polymers Rynite® 935—low warp, 35% mica/glass reinforced PET resin [10].

Figure 4.107 Flexural creep versus time at a stress of 27.6 MPa of DuPont Engineering Polymers Rynite® 940—low warp, 40% mica/glass reinforced PET resin [9].

4: POLYESTERS

189

Figure 4.108 Flexural creep modulus versus time at a stress of 27.6 MPa of DuPont Engineering Polymers Rynite® 940—low warp, 40% mica/glass reinforced PET resin [10].

Figure 4.109 Flexural creep strain versus time at various temperatures and at a stress of 27.6 MPa of DuPont Engineering Polymers Rynite® FR943—flame retardant, 43% mica/glass reinforced, higher heat, low warp PET resin [9].

190

THE EFFECT

OF

CREEP

AND OTHER

TIME RELATED FACTORS

ON

PLASTICS

AND

ELASTOMERS

Figure 4.110 Flexural creep modulus versus time at various temperatures and at a stress of 27.6 MPa of DuPont Engineering Polymers Rynite® FR943—flame retardant, 43% mica/glass reinforced, higher heat, low warp PET resin [10].

Figure 4.111 Flexural creep versus time at a stress of 27.6 MPa of DuPont Engineering Polymers FR946— flame retardant, 46% mica/glass reinforced, higher heat, low warp PET resin [9].

4: POLYESTERS

Figure 4.112 Flexural creep modulus versus time at a stress of 27.6 MPa of DuPont Engineering Polymers FR946—flame retardant, 46% mica/glass reinforced, higher heat, low warp PET resin [10].

Figure 4.113 Flexural creep versus time at a stress of 27.6 MPa of DuPont Engineering Polymers Rynite® SST35—super tough, 35% glass reinforced PET resin [9].

191

192

THE EFFECT

OF

CREEP

AND OTHER

TIME RELATED FACTORS

ON

PLASTICS

AND

ELASTOMERS

Figure 4.114 Flexural creep modulus versus time at a stress of 27.6 MPa of DuPont Engineering Polymers Rynite® SST35—super tough, 35% glass reinforced PET resin [10].

Figure 4.115 Flexural creep versus time at a stress of 27.6 MPa of DuPont Engineering Polymers Rynite® 545—general purpose, 45% glass fiber reinforced PET resin [9].

4: POLYESTERS

Figure 4.116 Flexural creep modulus versus time at a stress of 27.6 MPa of DuPont Engineering Polymers Rynite® 545—general purpose, 45% glass fiber reinforced PET resin [10].

Figure 4.117 Flexural creep strain versus time at a stress of 6.9 MPa of DuPont Engineering Polymers Rynite® 555—general purpose, 55% glass fiber reinforced PET resin [9].

193

194

THE EFFECT

OF

CREEP

AND OTHER

TIME RELATED FACTORS

ON

PLASTICS

AND

ELASTOMERS

Figure 4.118 Flexural creep strain versus time at a stress of 13.8 MPa of DuPont Engineering Polymers Rynite® 555—general purpose, 55% glass fiber reinforced PET resin [9].

Figure 4.119 Flexural creep strain versus time at a stress of 27.6 MPa of DuPont Engineering Polymers Rynite® 555—general purpose, 55% glass fiber reinforced PET resin [9].

4: POLYESTERS

Figure 4.120 Flexural creep modulus versus time at a stress of 6.9 MPa of DuPont Engineering Polymers Rynite® 555—general purpose, 55% glass fiber reinforced PET resin [10].

Figure 4.121 Flexural creep modulus versus time at a stress of 13.8 MPa of DuPont Engineering Polymers Rynite® 555—general purpose, 55% glass fiber reinforced PET resin [10].

195

196

THE EFFECT

OF

CREEP

AND OTHER

TIME RELATED FACTORS

ON

PLASTICS

AND

ELASTOMERS

Figure 4.122 Flexural creep modulus versus time at a stress of 27.6 MPa of DuPont Engineering Polymers Rynite® 555—general purpose, 55% glass fiber reinforced PET resin [10].

4.4 Liquid Crystalline Polymers Liquid crystalline polymers (LCPs) are a relatively unique class of partially crystalline aromatic polyesters based on 4-hydroxybenzoic acid and related monomers shown in Figure 4.123. Liquid crystal polymers are capable of forming regions of highly ordered structure while in the liquid phase. However, the degree of order is somewhat less than that of a regular solid crystal. Typically, LCPs have outstanding mechanical properties at high temperatures, excellent chemical resistance, inherent flame retardancy, and good weatherability. Liquid crystal polymers come in a variety of forms from sinterable high temperature to injection moldable compounds. LCPs are exceptionally inert. They resist stress cracking in the presence of most chemicals at elevated temperatures, including aromatic or

halogenated hydrocarbons, strong acids, bases, ketones, and other aggressive industrial substances. Hydrolytic stability in boiling water is excellent. Environments that deteriorate these polymers are high-temperature steam, concentrated sulfuric acid, and boiling caustic materials. As an example, the structure of Celanese Vectra® A950 LCP is shown in Figure 4.124. Manufacturers and trade names: Eastman Thermx®, Celanese Vectrant, Vectra® and Zenite®, Solvay Advanced Polymers Xydar®, Sumitomo Sumikasuper®, Toray Siveras®. Applications and uses: electrical parts, electronics (connectors, sockets, chip carriers), mechanical parts, food containers, automotive underhood parts, chemical processing, and household cookware for conventional and microwave ovens. Data for LCP plastics are found in Figures 4.125 4.131.

4: POLYESTERS

197

HBA 4-hydroxybenzoic acid HNA 6-hydroxynaphthalene-2-carboxylic acid

BP 4-(4-hydroxyphenyl)phenol HQ Benzene-1,4-diol (hydroquinone)

TA Benzene-1,4-dicarboxylic acid (terephthalic acid)

NDA Naphthalene-2,6-dicarboxylic acid

IA Benzene-1,3-dicarboxylic acid (isophthalic acid)

Figure 4.123 Chemical structures of monomers used to make LCP polyesters.

Figure 4.124 Chemical structure of Celanese Vectra® A950 LCP.

198

THE EFFECT

OF

CREEP

AND OTHER

TIME RELATED FACTORS

ON

PLASTICS

AND

ELASTOMERS

Figure 4.125 Flexural creep modulus versus time at various temperatures and 50 MPa stress of Celanese Vectra® A130—30% glass fiber reinforced, standard grade LCP resin [11].

Figure 4.126 Isochronous stress strain at 100°C after annealing at 250°C for 4 h of Celanese Zenite® 6130 BK010—30% glass reinforced LCP resin [12].

4: POLYESTERS

Figure 4.127 Isochronous stress strain at 100°C as molded Celanese Zenite® 6130 BK010—30% glass reinforced LCP resin [12].

Figure 4.128 Flexural creep modulus versus time at various temperatures and 50 MPa stress of Celanese Vectra® B130—30% glass fiber reinforced, high stiffness LCP resin [13].

199

200

THE EFFECT

OF

CREEP

AND OTHER

TIME RELATED FACTORS

ON

PLASTICS

AND

ELASTOMERS

Figure 4.129 Flexural creep modulus versus time at various temperatures and 50 MPa stress of Celanese Vectra® C130—30% glass fiber reinforced, heat resistant LCP resin [13].

Figure 4.130 Tensile creep modulus versus time at various temperatures and stress of Celanese Vectra® E130i—30% glass fiber reinforced, easy flow, high-temperature LCP resin [11].

4: POLYESTERS

201

Figure 4.131 Tensile creep modulus versus time at various temperatures and stress of Celanese Vectra® H140—40% glass fiber reinforced, highest temperature LCP resin [13].

4.5 PolycyclohexyleneDimethylene Terephthalate Polycyclohexylene-dimethylene terephthalate (PCT) is a high-temperature polyester that possesses the chemical resistance, processability, and dimensional stability of polyesters PET and PBT. However, the aliphatic cyclic ring shown in Figure 4.132 imparts added heat resistance. This puts it between the common polyesters and the LCP polyesters described in the previous section. This material has found use in automotive, electrical, and housewares applications. Manufacturers and trade names: Celanese Thermx®, Eastman Eastar®. Applications and uses: rigid medical, blister packaging, laundry bags, hospital bed pads. Data for PCT plastics is found in Figure 4.133.

4.6 Polyphthalate Carbonate Amorphous polyphthalate carbonate (PPC) copolymer is another high-temperature PC. It provides excellent impact resistance, optical clarity, and abrasion resistance. The plastic offers ultraviolet protection as well. It is lightweight, impact-

resistant, and can be reused after multiple exposures to sterilization. Its structure is shown in Figure 4.134. Manufacturers and trade names: SABIC Innovative Polymers Lexant. Applications and uses: medical devices. Data for PPC copolymer plastics are found in Figures 4.135 4.141.

4.7 Polyester Blends and Alloys There are numerous polyester blends and alloys based on polyesters. Often the different polyesters are blended. Manufacturers and trade names: Celanese Vandar®, SABIC Innovative Plastics Xenoy®, DuPont Crastin®, BASF Ultradur®. Applications and end uses: telephone line splice cases, switches, connectors, housings, improved impact brake and fuel line clips, wheel covers, headlamp bezels and covers, panels, power distribution boxes, cold temperature air bag doors, automotive safety systems, wheel covers, impact fascias, improved impact appliance lids, power tools, panels, housings. Data for polyester blends and alloys plastics are found in Figures 4.142 4.151.

202

THE EFFECT

OF

CREEP

AND OTHER

TIME RELATED FACTORS

ON

PLASTICS

AND

ELASTOMERS

Figure 4.132 Chemical structure of polybutylene PCT polyester.

Figure 4.133 Flexural creep at 80°C and various stress levels of Celanese Thermx® CG993 PCT resins [14].

Figure 4.134 Chemical structure of PPC polyester.

4: POLYESTERS

203

Figure 4.135 Creep strain versus time at 23°C of SABIC Innovative Plastics Lexan® PCC4701R PPC resin.

Figure 4.136 Creep strain versus time at 23°C of SABIC Innovative Plastics Lexan® 4501 PPC resin.

204

THE EFFECT

OF

CREEP

AND OTHER

TIME RELATED FACTORS

ON

PLASTICS

AND

ELASTOMERS

Figure 4.137 Creep strain versus time at 90°C of SABIC Innovative Plastics Lexan® 4501 PPC resin.

Figure 4.138 Creep strain versus time at 120°C of SABIC Innovative Plastics Lexan® 4501 PPC resin.

4: POLYESTERS

Figure 4.139 Creep strain versus time at 23°C of SABIC Innovative Plastics Lexan® 4704 PPC resin.

Figure 4.140 Creep strain versus time at 90°C of SABIC Innovative Plastics Lexan® 4704 PPC resin.

205

206

THE EFFECT

OF

CREEP

AND OTHER

TIME RELATED FACTORS

ON

PLASTICS

AND

ELASTOMERS

Figure 4.141 Creep strain versus time at 140°C of SABIC Innovative Plastics Lexan® 4704 PPC resin.

4.7.1 SABIC Innovative Plastics Polyester Blend Resins SABIC Vandar®

Figure 4.142 Creep strain versus time at 23°C and various stress levels of SABIC Innovative Plastics Valox® 508—PBT/PC polyester blend resin.

4: POLYESTERS

207

Figure 4.143 Creep strain versus time at 60°C and various stress levels of SABIC Innovative Plastics Valox® 508—PBT/PC polyester blend resin.

Figure 4.144 Creep strain versus time at 82°C and various stress levels of SABIC Innovative Plastics Valox® 508—PBT/PC polyester blend resin.

208

THE EFFECT

OF

CREEP

AND OTHER

TIME RELATED FACTORS

ON

PLASTICS

AND

ELASTOMERS

Figure 4.145 Creep strain versus time at 121°C and various stress levels of SABIC Innovative Plastics Valox® 508—PBT/PC polyester blend resin.

Figure 4.146 Creep performance versus time at room temperature and different stress levels of standard SABIC Innovative Plastics Xenoy® PC/PBT/PET resin as a function of time [15].

4: POLYESTERS

209

Figure 4.147 Creep strain versus time at 23°C and various stress levels of SABIC Innovative Plastics Xenoy® 6370—30% glass fiber filled, impact modified PBT/PC alloy.

Figure 4.148 Creep strain versus time at 60°C and various stress levels of SABIC Innovative Plastics Xenoy® 6370—30% glass fiber filled, impact modified PBT/PC alloy.

210

THE EFFECT

OF

CREEP

AND OTHER

TIME RELATED FACTORS

ON

PLASTICS

AND

ELASTOMERS

Figure 4.149 Creep strain versus time at 90°C and various stress levels of SABIC Innovative Plastics Xenoy® 6370—30% glass fiber filled, impact modified PBT/PC alloy.

4.7.2 DuPont Engineering Polymers Crastin® Polyester Alloys

Figure 4.150 Isochronous stress versus strain at 23°C of DuPont Engineering Polymers Crastin® LW9020—20% fiber glass reinforced PBT PBT/ASA alloy.

Figure 4.151 Isochronous stress versus strain at 23°C of DuPont Engineering Polymers Crastin® LW9030—30% fiber glass reinforced PBT PBT/ASA alloy.

4: POLYESTERS

References [1] Lexan resin PC resin product brochure, SABIC Innovative Plastics, 2008. [2] Physicality Novarex®, Iupilon®, Mitsubishi Engineering-Plastics Corporation, 2010. [3] Celanex® Impet® Vandar® Thermoplastic polyesters Europe brochure, Ticona, 2008. [4] Polyester technical manual polyester products Celanex® PBT Impet® PET Vandar® PBT, Celanese, 2013. [5] Designing with Celanex®, Vandar®, Impet ® & Riteflex® Thermoplastic polyesters design manual (PE-10), Ticona, 2010. [6] VESTODUR polybutylene terephthalate, Degussa, 2001. [7] Ultradur® polybutylene terephthalate (PBT), BASF, 2008.

211

[8] About NOVADURAN, Mitsubishi Engineering-Plastics Corporation, 2011. [9] Crastin® PBT and Rynite® PET Design Information, DuPont, 2004. [10] Design guide—module IV Rynite® PET, DuPont, 1997. [11] Vectra® liquid crystal polymer (LCP), Celanese, 2012. [12] DuPontt Zenite® LCP liquid crystal polymer resin product guide and properties, DuPont, 2003. [13] Vectra® liquid crystal polymer (LCP), Celanese, 2001. [14] Thermx® PCT high-performance polyester November 2010, Ticona/Celanese 2010. [15] Xenoy PC/PBT/PET resin product guide, GE Plastics, 2005.