Polyamide-imide tensile strength

Both polyamide-imide and polyetherimide have high heat distortion temperature, tensile strength, and modulus. Polyamide-imide is useful from cryogenic temperatures up to 260°C. It is virtually unaffected by aliphatic and aromatic chlorinated and fluorinated hydrocarbons and by most acid and alkali solutions. These polymers are used in high-performance electrical and electronic parts, microwave appliances, and under-the-hood automotive parts. Typical automotive applications include timing gears, rocker arms, electrical connectors, switches, and insulators. 

Polyamide-imides enjoy exceptional thermal stability with a decomposition onset at 500°C and 10% weight loss at 540 C. Long-term aging at high temperatures (250°C) shows only a 80 to 90% drop in tensile strength after 10,000 h (see Fig. 12.19). The UL relative thermal index (RTl) predicts 100,000 h of useful life at temperatiures as high as 220°C. 

Polymers of excellent tensile strength (i.e., >100 MPa) inclnde epoxies, polyester laminates, polyamide (PA) 4/6, polyamide-imide, and polyvinylidene flnoride. 

Reinforced polymers that combine high tensile strength with high flexural modulus include polybutylene terephthalate, polyether ether ketone, polyamide-imide, and polyethylene terephthalate (see Table 3.3). 

The corporation of glass fiber has little effect on the tensile strength of polyamide-imide from 185 to 195 MPa (Table 3.1) and the flexural modulus from 4.6 to 11.1 GPa (Table 3.2), while the elongation of break decreases from 12% to 5% (Table 3.4). 

Tensile strength profile of polyamide imide with 3% Ti02 and 0.5% PTFE during aging at 250 °C (specimen thickness 3.2 mm) [572]... 

Various approaches have been undertaken for reactive compatibilization of poly-amide/ABS alloys. Maleic anhydride can be grafted to the ABS. Styrene maleic anhydride (SMA) copolymers have been employed as compatibilizers for polyamide/ABS blends. SMA and SAN copolymers are miscible when the AN and maleic anhydride (MA) contents are equal. The impact strength of these blends has been found to be sensitive to the amount and composition of the SMA copolymer. Addition of SMA to SAN/polyamide blends was found to enhance the tensile and impact properties of these blends. Imidized acrylic polymers have been used as compatibilizers for nylon-6/ABS blends. Glycidyl methacrylate and methyl methacrylate (GMA/MMA) copolymers are used as compatibilizing agents. The epoxide functionality in GMA is capable of reaction with polyamide end groups. GMA/MMA copolymers can be shown to be miscible with SAN over the range of AN content of ABS. Styrene/GMA copolymers have been reported to be used as compatibilizers for polymer pairs such as... 

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