GB1241302A - Heat-sensitive high molecular weight resistors - Google Patents

Abstract

1,241,302. Polymer compositions. MATSUSHITA ELECTRIC INDUSTRIAL CO. Ltd. 22 July, 1968 [3 Aug., 1967 (2); 24 June, 1968 (2)], No. 34966/68. Heading C3B. [Also in Division H1] A heat-sensitive high-molecular-weight resistor comprises a copolymer or high polymer composition which contains a charge transfer bond in an amount to give said polymer or composition a volume resistivity of at least 10<SP>2</SP> ohm. cm. at 30‹ C. and a thermistor temperature coefficient of at least 1000‹ K between 30‹ and 60‹ C. Either the donor or the acceptor or both may be polymers. Examples of highmolecular-weight donors are polymers of 2- or 4-vinyl pyridine, 1-vinyl-2-methylimidazole, N- vinyl - carbazole, N - vinylthiocarbazole or N- vinyl pyrrolidone. Examples of highmolecular-weight acceptors are polymers of tri- or di-nitrostyrene, phathalic anhydride or maleic anhydride. Binary or tertiary copolymers of the above donors and acceptors together with styrene, methyl, ethyl, butyl or ethyl hexyl acrylate, methyl methacrylate, acrylonitrile, vinyl acetate or octylvinyl ether are also specified. Low-molecular-weight donors may be perylene, p-phenylenediamine, diphenylamine or 1-naphthylamine whilst the lowmolecular-weight acceptors may be chloranil, bromanil, tetracyanoethylene, tetracyano-pquinodimethane, hexacyanobutadiene, hexachlorobutadiene or tetracyanobutadiene. The composition may be a polymeric matrix containing a dispersion of a charge transfer complex wherein the polymer is preferably PVC, or a copolymer of ethylene and ethyl acrylate; styrene and butadiene, ethylene and vinyl acetate, styrene, 2-ethylhexyl acrylate and butyl acrylate or styrene, butadiene and acrylonitrile. The charge transfer complex dispersed in the above polymers may be one of high molecular weight as specified above together with dioctyl phthalate and tribasic lead sulphate or dimethyl cetyl benzyl ammonium tetracyano-p-quinodimethane, stearamide propyl dimethyl - # - hydroxyethyl ammonium tetracyano - p - quinodimethane, # - hydroxyethyl-2- methyl imidazolium tetracyanoquinodimethane, 2 - undecyl imidazolium tetracyanoquinodimethane, or bis - (di - # - hydroxyethylaminoethyl) - o - phthaldiamide tetracyano - p - quinodimethane. The conduction is said to be electronic not ionic. An epoxy resin composition comprises the condensate of bisphenol A and epichlorhydrin and stearamide - propyl - dimethyl - hydroxyethyl - ammonium tetracyano - p - quinodimethane which is an electroconductive curing agent and a charge transfer complex.