New glass fibre reinforced polyether TPUs - Plasticker

Thermal expansion comparable
with metals
The new TPUs exhibit good UV stability,
alongside high heat distortion temperatures.
Some values of over 126 °C have been obtained
in heat distortion temperature (HDT)
testing according to DIN EN ISO 75/1-3,
Method A, at 1.8 Mpa load, as well as 174 °C
under Method B at 0.45 MPa load (tab. 1).
Thermal expansion is signifi cantly lower than
for many other plastics and approaches that
of metals. Coeffi cients of thermal expansion
are comparable with those of aluminium. It
is therefore easier with the new ether TPUs
to design narrow gaps between adjacent
parts of assembled components (zero-gap
appearance). This is important in automotive
engineering or in high-end equipment
with demanding design features.
As the new TPUs are based on materials
such as polyetherdiols, they are more resistant
against microbes and decomposition
through hydrolysis compared with their
polyester based “siblings”. This also applies
for permanent contact with seawater. Their
fl ow capability and precision in reproduction
of surface structures are both at a high
level. They may be easily painted and printed.
Compared with other plastics, they dampen
noise very effectively. Relatively low density
of 1.3 g/cm 3 facilitates economic production
of components through low weight of the
material consumed.
High load bearing
The polyether TPUs have potential for
applications involving mainly components
exposed to high mechanical load and that
also have to perform well at low temperatures.
This applies, e. g. for functional parts
of sports articles such as ski tips (fi g. 1),
covers, binders, goggles and edge protectors,
functional parts in ski shoes, technical
functional parts, as well as housings for
Tab. 1: Properties of Desmovit R glass fi bre reinforced polyether TPU (n. b. = no breakage) (Source: geba)
agricultural and building construction machinery.
There are also large opportunities
in riding and motor sport protection, safety
helmets, as well as housings and switches
for household appliances and electric tools.
The high seawater resistance, cold impact
strength and shock resistance predestine the
new TPUs equally well for use in ship equipment
and in the fi shing industry – such as
for fi shing net weights.
Their application in the offshore area is
especially attractive. They lend themselves
for example as housing materials for geophysical
measurement probes. Such components
sometimes spend more than a year
in seawater – often in polar regions – and
may not fail, on account of the enormous
costs for repair and replacement. With wear
resistance, fl exibility and seawater resistance,
the new TPUs are suitable in addition
as material for production of zips for
divers’ suits. On account of noise-dampening
properties, they are also an interesting
Properties Test conditions Unit Standard DP R 9918 DP R 9920 DP R 9924 DP R 9929 DP R 9930
Mechanical properties
Tear resistance 200 mm/min MPa ISO 527 59 59 67 71 73
Elongation at break 200 mm/min % ISO 527 17 14.5 10 8 6
Flexural modulus 1 mm/min 23 °C MPa ISO 178 1,800 2,000 2,400 2,900 3,000
Flexural modulus 1 mm/min –30 °C MPa ISO 178 3,000 3,500 3,900 4,300 4,600
Bending strength 2 mm/min 23 °C MPa ISO 178 54 60 68 78 87.2
Bending strength 2 mm/min –30 °C MPa ISO 178 118 131 142 154 161
Charpy impact strength 23 °C kJ/m2 ISO 179/1eU n. b. n. b. n. b. 75 60
Charpy impact strength –30 °C kJ/m2 ISO 179/1eU n. b. n. b. n. b. 82 70
Charpy notched impact strength 23 °C kJ/m2 ISO 179/1eA 45 40 33 26 18
Charpy notched impact strength –30 °C KJ/m2 ISO 179/1eA 22 20 15 14 8.5
Shore hardness
Thermal properties
Shore D ISO 868 D 64 67 68 68 71
Heat distortion temperature, method A 1.8 MPa ISO 75/1-3 126 119 126 122 121
Heat distortion temperature, method B 0.45 MPa ISO 75/1-3 167 156 172 161 174
Vicat softening temperature
Other properties
50 N, 50 °C/h ISO 306 B 92 94 105 104 115
Density g/cm3 ISO 1183-1-A 1.29 1.3 1.31 1.32 1.31
Abrasion mm3 ISO 4649 80 78 82 83 102
Linear expansion coeffi cient longitudinal ppm/K DIN 53752-A 10.3 10.3 7.2 9.6 13.7
Linear expansion coeffi cient transverse ppm/K DIN 53752-A 114 114 120 117 123
Shrinkage after conditioning longitudinal % 0.1 0.12 0.12 0.13 0.2
Shrinkage after conditioning
Processing guidelines
transverse % 0.32 0.51 0.36 0.38 0.58
Injection moulding melt temperature °C 200 – 230
Injection moulding tool temperature °C 40 – 80
Drying temperature (dry air drier) °C 120 – 130 (2 h residual moisture < 0.03 %)
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