Joseph Alvin Venable

US Patent:

42882532, Sep 8, 1981

Filed:

Jun 8, 1979

Appl. No.:

6/046848

Inventors:

Joseph M. Venable - New Braunfels TX

Assignee:

Pamrod, Incorporated - McQueeney TX

International Classification:

C04B 4300

US Classification:

106 84

Abstract:

Improved water insensitive bonded perlite structural materials are produced by combining expanded perlite with an aqueous solution of an alkali metal silicate and thereafter molding the mixture into a desired shape and curing the molded mixture under closely controlled temperature and humidity conditions. The aqueous solution of alkali metal silicate will be either a sodium silicate solution or a potassium silicate solution. The temperature and humidity conditions for curing the molded perlite and alkali metal silicate mixture are from about 180. degree. F. to about 225. degree. F. and from about 30% to about 60% relative humidity. By carrying out the curing process under the closely controlled temperature and relative humidity conditions, a water insoluble crystalline reaction product is formed between the alkali metal silicate and the reactive expanded perlite.