Zenas S Crocker

US Patent:

41428048, Mar 6, 1979

Filed:

Dec 20, 1977

Appl. No.:

5/862596

Inventors:

Zenas Crocker - Wellesley Hills MA

Assignee:

Lewis Specialties Limited - Montreal

International Classification:

B29B 106

US Classification:

366 77

Abstract:

A process and apparatus for fluxing a mixable thermoplastic material is disclosed. In the process a blend of thermoplastic material is agitated in a mixer; at the same time vibrations of the mixer is monitored during this agitation step and when it reaches a predetermined level, a signal is generated so the mixer may be stopped or the material discharged. The apparatus includes a high intensity mixer, a means for monitoring vibrations of the mixer, together with a means for comparing these vibrations with a preset level to produce a signal to indicate the material in the mixer has reached the required degree of fluxing.

US Patent:

44204493, Dec 13, 1983

Filed:

Apr 19, 1982

Appl. No.:

6/369584

Inventors:

Zenas Crocker - Osterville MA
A. Nelson Wright - St. Agathe des Monts, CA

Assignee:

Synergistics Chemicals Limited - Concord

International Classification:

B29C 1902

US Classification:

264 68

Abstract:

A process for producing articles of polytetrafluoroethylene (PTFE) is disclosed. The process allows some of the conventional plastic fabrication techniques to be used with PTFE which until now have not been possible. The process comprises the steps of intensively mixing and thermokinetically heating PTFE resin in an enclosed container with a plurality of blades attached to arms rotating about an axis, with a blade tip speed of at least 30 meters/second, to a predetermined discharge temperature of above 370. degree. C. , discharging the resin at the discharge temperature, forming the resin into a desired shape at a temperature at or below the discharge temperature, holding the resin in the desired shape above a predetermined forming temperature for a predetermined time, and cooling the resin in the desired shape.