Process for producing articles of ultra high molecular weight high density polyethylene
AssigneeSynergistics Chemicals Limited
InventorZenas Crocker
Life of this patent
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Abstract
A process for producing articles of ultra high molecular weight high density polyethylene is disclosed which avoids long heating and cooling cycles, and compacting pressures in the order of 3,000 to 4,000 lbs/sq. inch. The resin is intensively mixed and thermokinetically heated in an enclosed container with a plurality of blades attached to arms rotating about an axis with a blade tip speed of at least 18 m/sec. until the resin reaches a desired discharge temperature of at least 135.degree. C. After being discharged from the mixing step, the ultra high molecular weight resin is formed into the desired shape within a time such that degradation does not occur.
Claims17
A process for the production of a fabricated article of a desired shape from ultra high molecular weight high density polyethylene having a molecular weight greater than 1.7.times.10.sup.6 comprising the steps of:
- intensively mixing and thermo-kinetically heating ultra high molecular weight polyethylene 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 18 m/second, the resin is heated quickly at a desired discharge temperature of at least 135.degree. C. without shearing action occurring and with thermal degradation being controlled, discharging the resin after the intensive mixing step, and forming the ultra high molecular weight polyethylene resin into the desired shape within a time such that degradation does not occur.
Dependencies are inferred from the claim text.