Mechanical properties and methods of production of high-modulus films based on polyimide blends

High-performance aromatic polyimides for inertial confinement fusion experiments

“…As previously shown, 5,8 the relationship between polyimide blend composition and mechanical parameters is not exactly linear. However, these results provide further evidence that these polyimide blends are dispersed at the molecular level because they exhibit copolymer behaviour.…”

Synthesis and properties of polyimides-containing benzoxazole units in the main chain

“…2 Uniaxial or biaxial predrawing of the polyamide acid (PAA; a PI precursor) film is an effective way to promote the degree of molecular orientation, thus making the PI films have improved thermodimensional stability, mechanical property and more resistance toward chemical and thermal attack. 3–5 However, the pre-drawing procedure of the film requires precise control of process parameters, which is complex and costly, besides, even if ideal stretching process was possible, such mechanical steps could not be applied to the film/substrate laminates demanded in microelectronic applications. 6…”

Morphology and mechanical properties of polymer-inorganic nanocomposite containing triple chain fibrous Na-Mg hydrosilicate

“…Simultaneous increase of the stiffness and the elongation of the specimen could be ascribed to the macromolecules orientation under conditions of the experiment. It has been earlier demonstrated that the increase in the dynamic mechanical modulus of the rigid-chain polyimide films along the uniaxial stretching direction is due to the molecules orientation rather than the increased degree of crystallinity [31]. For the polyimides it has been shown that the domains growth and the macromolecules ordering inside the domain upon the uniaxial stretching are observed at relatively low temperatures (below the polymer T g ) and deformations [32,33].…”