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What is the Polyurethane (PUR) thermoplastic elastomere ?
General
Polyurethane has become increasingly important in the cable industry over the past years. This material shows at certain temperatures mechanical characteristics similar to rubber. The combination of thermoplastic and elastic characteristics has led to the description TPE thermoplastic elastomere. Here at SAB Bröckskes GmbH & Co KG, we use PUR on a Polyether base as sheath material. In addition to standard Polyurethane, thanks to constant development between SAB Bröckskes and the plastic industry, the following types of PUR are also available:
PUR semi-mat (low adhesion)
PUR mat (rough surface, low adhesion)
PUR flame protected
PUR halogen-free and flame protected
Mechanical characteristics
The insulation materials of the cables are usually not subject to high mechanical stress. Sheaths, on the other hand are heavily used. This is especially true for flexible control and connection cables which are often pulled over sharp corners and rough surfaces. This can lead to cuts which are accentuated when the cable is stretched during flexible use. Compressive stress caused by squashing and impacting from tools and machines can also occur. The most important mechanical characteristics of PUR are:
high tensile strength
high tear resistance
notch resistance
abrasion resistance
alternate bending resistance
impact resistance
flexibility at low temperatures
Chemical resistance
The chemical resistance depends upon many factors such as chemical type, reaction time, temperature, volume, concentration and of course the type of Polyurethane used. In comparison with many other materials, such as rubber or PVC, PUR has a better resistance against chemical reaction. The outstanding chemical characteristics are:
very good resistance against mineral oils
good resistance against alcohol-free benzine
good resistance during storage in water
good resistance against many solvents
The danger of decomposition through microbes exists with Polyurethane on a Polyester base after prolonged exposure to dampness and warmth. The Polyurethane on a Polyether base used by SAB is resistant to microbic decomposition. Etherpolyurethane and Esterpolyurethane can be differentiated by the saponification value (VZ).
Etherpolyurethane (resistant) - VZ ≤ 200
Esterpolyurethane (non-resistant) - VZ ≥ 350
After prolonged exposure to warm water or tropical climates, Polyurethane on a Polyester base will undergo a chemical reaction. The result is a weakening of mechanical strength. SAB Polyurethane on a Polyether base is relatively more resistant to hydrological break-down.
Etherpolyurethane is weather and ozone resistant in all climates. Discolouration by sunlight is possible, but this will not affect performance.
source : What is the Polyurethane (PUR) thermoplastic elastomere ?]General
Polyurethane has become increasingly important in the cable industry over the past years. This material shows at certain temperatures mechanical characteristics similar to rubber. The combination of thermoplastic and elastic characteristics has led to the description TPE thermoplastic elastomere. Here at SAB Bröckskes GmbH & Co KG, we use PUR on a Polyether base as sheath material. In addition to standard Polyurethane, thanks to constant development between SAB Bröckskes and the plastic industry, the following types of PUR are also available:
PUR semi-mat (low adhesion)
PUR mat (rough surface, low adhesion)
PUR flame protected
PUR halogen-free and flame protected
Mechanical characteristics
The insulation materials of the cables are usually not subject to high mechanical stress. Sheaths, on the other hand are heavily used. This is especially true for flexible control and connection cables which are often pulled over sharp corners and rough surfaces. This can lead to cuts which are accentuated when the cable is stretched during flexible use. Compressive stress caused by squashing and impacting from tools and machines can also occur. The most important mechanical characteristics of PUR are:
high tensile strength
high tear resistance
notch resistance
abrasion resistance
alternate bending resistance
impact resistance
flexibility at low temperatures
Chemical resistance
The chemical resistance depends upon many factors such as chemical type, reaction time, temperature, volume, concentration and of course the type of Polyurethane used. In comparison with many other materials, such as rubber or PVC, PUR has a better resistance against chemical reaction. The outstanding chemical characteristics are:
very good resistance against mineral oils
good resistance against alcohol-free benzine
good resistance during storage in water
good resistance against many solvents
The danger of decomposition through microbes exists with Polyurethane on a Polyester base after prolonged exposure to dampness and warmth. The Polyurethane on a Polyether base used by SAB is resistant to microbic decomposition. Etherpolyurethane and Esterpolyurethane can be differentiated by the saponification value (VZ).
Etherpolyurethane (resistant) - VZ ≤ 200
Esterpolyurethane (non-resistant) - VZ ≥ 350
After prolonged exposure to warm water or tropical climates, Polyurethane on a Polyester base will undergo a chemical reaction. The result is a weakening of mechanical strength. SAB Polyurethane on a Polyether base is relatively more resistant to hydrological break-down.
[url=http://www.sab-cable.com/cables-wires-harnessing-temperature-measurement/technical-data/general-information-pur/]What is the Polyurethane (PUR) thermoplastic elastomere ? (http://general