New or improved materials and moulded bodies of high electrical and thermal conductivity and high chemical resistance and a process for the manufacture thereof

摘要

A conducting material, heat and pressure moulded under conditions preventing or inhibiting lateral spreading of the moulded substance and having a specific resistance below 0,1 Ohm. cm. comprises an aggregate of graphite particles, the majority of which have a smaller overall anisotropy than a single crystal of graphite, which aggregate has been compressed under substantially solvent-free conditions, and as binder for the aggregate 5 to 30% wt. of a heat and chemical resistant thermoplastic resin which softens over a range of at least 2 DEG C., the anisotropy of the macro-structure of the total material corresponding to a preferential crystallographic orientation of the crystallites of not more than 30%, the degree of orientation in the material being defined as the distribution of 002 planes in all possible angular positions. Suitable graphite particles are derived from waste graphite powder. Resins specified are polymers of halo-hydrocarbons, e.g. polyvinyl chloride, polytrifluoromonochloroethylene and polytetrafluoroethylene. The material may be used in the construction of chemical apparatus or as an electrode. Composite moulded bodies are claimed wherein the material of the invention is used to form an electrode which is integrally moulded with a holder constituted by a material comprising the same components but differing in resin content, size and size distribution of graphite particles and shape of graphite particles and degree of compression, e.g. that described and claimed in Specification 928,352. Graphs (not shown) are provided showing how the graphite particle size distribution, moulding temperature and pressure, and resin content affect the resistivity, porosity and strength of the product. Nearly all the points plotted correspond with products not satisfying the resistivity requirement of Claim 1 but it is stated that by correlating the graphs combinations of factors providing the products claimed can be predicted. Specifications 653,367 and 729,321 also are referred to.