Polyamide Elastomers:
OR
1. The reaction of dicarboxylic acid polyamide blocks with diamide polyether blocks or diamine polyamide block with dicarboxylic polyether blocks in molten state give polyamide ether block elastomer
HOOC-PA-COOH + H2N-PE-NH2
HO - CO-PA-CO-NH-PE-NH- H
H2N-PA-NH2 + HOOC-PE-COOH
H - NH-PA-NH-CO-PE-CO- OH
2. The reaction of poly(oxyethylene) diisocyanate with a diamine aromatic polyamide to form polyamide polyether block copolymers with urea linkages.
Chemistry & Structure:
1. The polyether amide block is obtained by the molten state polycondensation of polyetherdiol blocks and dicarboxylic amide blocks.
HO - CO-PA-CO-OPE-O-H
2. Dicarboxylic polyamide blocks are produced by the reaction of polyamide with dicarboxylic chain.
3. The structure of polyether block amide comprises linear and regular chains of rigid polyamide segment and flexible polyether segments
General properties:
1. The polyamide elastomers are low density, high elongation materials with solvent and abrasion resistance.
2. Polyamide elastomers are characterized for high abrasion and excellent fluid resistance
3. Available in wide range of hardness by copolymerising with flexible polyethers or polyether- esters.
Processing:
1. All grades of thermoplastic polyamide must be adequately dried before the use (80 C for 4 hrs).
2. During processing upto 20% regrind materials can be used.
3. These materials are easy to process and can be processed by extrusion moulding, rotational moulding and thermoforming etc.,
Applications:
1. End use for polyamide elastomers include sporting goods, automotive applications, hydraulic and pneumatic equipments, polymer modification, cable jacketing and tubing, medical applications and miscellaneous consumer products.
2. Automotive applications are limited to items that are not under the hood because of the materials low heat stability.
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