Polyamide/rubber

This route has only been developed during the 1980s and has proved of particular interest in the manufacture of thermoplastic polyamide rubbers. 

Other companies interested in thermoplastic polyamide rubbers have been Dow (following on work by Upjohn) and Akzo, whose initial development grades have been trade marked Ametal. 

PEBA thermoplastic polyamide rubber, polyether block amide... 

Thermoplastic polyester rubbers are also block copolymers of polyethers and polyesters. The polyester groups are capable of crystallisation and the crystal structures act like cross-links. These materials have good hydrocarbon resistance. Similar thermoplastic polyamide rubbers are also now available. 

Polyamide/rubber blends, 20 361 Polyamide block copolymers, 24 704, 708 Polyamide composite membranes, 21 633 Polyamide-elastomer block copolymers, 24 698... 

MAJOR USES Used in the production of polyurethane foams, dyes, isocyanate resins, polyamides, rubber and elastomeric fibers antioxidant for lubricating oils corrosion preventative curing agent. 

Figure 7.8 [17] shows the relationship between the viscosity ratio of a polyamide-rubber binary blending system and the size of domain particles obtained by mixing and kneading with a twin screw extruder [16-18]. Generally, it is easier to obtain the fine domain size under conditions where the two melt viscosities are close. Furthermore, the domain size reduction easily occurs when the surface tension tt between each polymer particle is low, even if there exists a considerable melt-viscosity difference. This means that both the addition of a compatibilizer or interfacial copolymerization reactions result in lower surface tension and, consequently, the domain size reduction is effectively accelerated. To analyze the domain size in polyblending, the Weber Number Wg or the following modified... 

Yoko F and Chiaki T (1983) Stabilizers for polyester-polyether-polyamide rubbers, JP Patent 60 053,558, to Toray Ind., Chem Ahstr 103 143217. 

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