Polymer Engineering and Science · 1988 · 83 citations · 13 references
EngineeringResponsive PolymersChemistryPolymersPolymer MaterialPolymer TechnologyPolymer ProcessingHybrid MaterialsThermal StabilityPolymer ChemistryMaterials ScienceMaterials EngineeringVarious Aromatic PolyimidesPolymer EngineeringPolymer AnalysisChemical StructuresPolymer ScienceFlexible LinkagePolymer CharacterizationPolymer PropertyFunctional Materials
Abstract The relationships, between chemical structures of various aromatic polyimides and their thermal expansion coefficients, were investigated and the properties of low thermal expansion polyimides were elucidated. Such low values were observed for polyimides obtained from pyromellitic dianhydride or 3,3′,4,4′‐biphenyltetracarboxyIic dianhydride and aromatic diamines, which included only benzene or pyridine rings fused at para‐positions without a flexible linkage. It was proposed that these low thermal expansion coefficients were related to the linearity of their polymer molecular skeletons. In particular, PIQ‐L100 (Hitachi Chemical Co. Ltd) is one such low thermal expansion polyimide and, it has excellent mechanical properties, thermal stability, and low absorbed moisture content.
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