Polyimide tensile strength

Polyimide Tensile Strength (MPa) Flexural Modulus (GPa) Heat Deflection Temperature (°Cat 1.8 MPa) Continuous Use Temperature (°o... 

BiaxiaHy oriented films have excellent tensile strength properties and good tear and impact properties. They are especially well regarded for their brilliance and clarity. Essentially all poly(ethylene terephthalate) film is biaxiaHy oriented, and more than 80% of polypropylene film is biaxiaHy oriented. Polystyrene film is oriented, and a lesser amount of polyethylene, polyamide, poly(vinyl chloride), and other polymers are so processed. Some of the specialty films, like polyimides (qv), are also oriented. 

Figure 4.124. Polyimide retention of tensile strength and elongation at break versus Weather-Ometer exposure time (h)...

Likewise, the mechanical properties of the copolymers were nearly identical or even somewhat enhanced towards the polyimide homopolymer in terms of the modulus and tensile strength values [44,47]. For most of the block copolymers, the elongations to break were substantially higher than that of PMDA/ODA polyimide (Table 4). The shape of the polyimide stress-strain curve is similar to that of a work-hardened metal with no distinguishable yield point... 

The fact that the polyimide based on diphenyloxidetetracarboxylic acid dianhydride is soluble in phenolic solvents enabled the authors to prepare (using solutions of this polymer in w-cresol and mixed trichloroethane/phenol solvent) almost colourless films showing (at 25 °C) a tensile strength of 114 MPa and a 9% elongation at break. 

The mechanical properties of the polyimide films (the sample size 10-mm length, 10-mm width) were examined at room temperature using a specially made machine with a constant drawing rate of 1 mm min"1. A profile of elongation vs. load for PI(BHDA+BBH) film is shown in Figure 4. The polyimide film possessed a tensile modulus of 2.1 GPa and a tensile strength of 52 MPa, and these values can compete in terms of strength with those of a commercial polycarbonate (PC).[8] The authors believe that this is the first example of a fully alicyclic polyimide for which the mechanical property was evaluated. 

The physical properties of polypropylene, poly(ethylene terephthalate), and polyimide are greatly influenced by orientation of the polymer. Polypropylene and poly(ethylene terephthalate) become highly crystallized upon stretching. Oriented, crystalline poly(ethylene terephthalate), for example, has significantly higher modulus, tensile strength, and continuous use temperature than its extruded, unoriented analog (see Table II). 

The fibres are surface treated during manufacture to prepare adhesion with the polymer matrix, whether thermosetting (epoxy, polyester, phenoUc and polyimide resins) or thermoplastic (polypropylene. Nylon 6.6, PMMA, PEEK). The fibre surface is roughened by chemical etching and then coated with an appropriate size to aid bonding to the specified matrix. Whereas composite tensile strength is primarily a function of fibre... 

Polyimide Final cure temperature (°C) Tensile strength (kgf/mm ) 5% Tensile stress (kgFmm") Elongation at break (%) Elastic modulus (kgFmm ... 

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