Dimensionally stable polyimides and related method

It is a film is disclosed, which comprises 40-100 wt .-% polyimide. The polyimide derived from a dianhydride component and a diamine component. The dianhydride component consisting of at least 3,3 ', 4,4'-biphenyltetracarboxylic dianhydride (BPDA) and optionally also from pyromellitic dianhydride (PMDA) in a molar ratio of 50-100: 50-0 (BPDA: PMDA). The diamine component comprises 1,5-naphthalene diamine (1,5-ND) and 1,4-diaminobenzene (PPD) and / or metaphenylene diamine (MPD) in a molar ratio of 15-95: 85-5 (1,5-ND : PPD + MPD) on. The films show an exceptional high temperature storage modulus (modulus of elasticity) and exceptionally low high-temperature creep (e