P h y s i c a l

C o n s t a n t s

o f

P o l y ( o x y t e t r a m e t h y l e n e - o x y t e r e p h t h a l o y l ) a n d

C o p o l y m e r s

O x i d e

w i t h

T e t r a m e t h y l e n e

T h e r m o p l a s t i c

E l a s t o m e r s *

K. B. W a g e n e r Department of Chemistry and Center for Macromolecular Science & Engineering, University of Florida, Gainesville, FL, USA

The literature gives different chemical abbreviations for this segmented polyester/polyether copolymer, such as PBT/ PTMO, PBT/PTHF (where PTHF abbreviates polytetrahydrofuran), and PBT/POTM (where POTM abbreviates polyoxy-tetramethylene). Occasionally, components of the

abbreviation are reversed (as in PTHF/PBT). All these abbreviations represent the same copolymer, which is available with different weight percentages of polyether being present.

Weight percentage polyether in copolymer a Property Hardness, shore D Density (mg/m 3 ) Coefficient of expansion (vol/K) @-20°C 2O0C 8O0C

0%b

10%

25%

35%

50%

60%

80 1.30

74 1.27

63 1.23

55 1.20

45 1.16

38 1.12

210 x 1 0 - 6 210 x 10 ~6

240 x 10 ~6 330 x 10 ~6 510 x 10 ~6

360 x 10 ~6 420 x 10 ~6 540 x 10 ~6

300 x 10 ~6 450 x 10 ~6 600 x 10 " 6

480 x 10 ~6

660 x 10 ~6

55 /48 C 1.35 223 54

44 /24 C 1.61 221 60

2 / - 28 C 1.72 210 41

- 23 / - 46 C 1.78 202 38

- 50 1.95 183 29

- 60 2.01 192 25

3.0 0.002 5.10 x 10 14

3.35 0.037 8.8 x 10 13

4.1 0.017 1.2 x 1 0 n

4.3 0.012 2.5 x 10 10

4.5 0.006

4.5 0.005

200 52

360 45

540 38

570 32

700 21

650 17

2600 2.74 0.78 0.011

830 2.70 1.58 0.076

300 2.17 0.96 0.062 40

170 1.94 0.48 0.035 53

90 1.60 0.08 0.03 60

53 1.25 -0.27 0.03 65

THERMAL PROPERTIES Glass transition temp. ( 0 C) Heat capacity, Cp (kJkg/K) @ 1000C Melting temperature (°C) Heat of fusion (kJ/kg) ELECTRICAL PROPERTIES Dielectric constant (1 kHz) Dissipation factor (1 kHz) Volume resistivity (ohm m) MECHANICAL PROPERTIES Ultimate elongation (%) (ASTM D 412) Tensile strength (MPa) (DIN 53504) Initial slope of stress-strain curve, Young's modulus (MPa) Storage modulus G' (log MPa) Loss modulus G" (log MPa) Loss tangent G "IG1 Resilience (rebound) (%) a b c d

Mn = 1000 for the polyether except for the 60 wt.% copolymer, in which Mn = 2000. 0% refers to the properties for pure poly(oxytetramethylene-oxyterephthaloyl) (poly(butylene terephthalate)). Two different measurement values are given, top tan