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US 4,483,333 AGranted
Orthopedic cast
AssigneeWRF/Aquaplast Corporation
InventorLloyd H. Wartman
Life of this patent
Estimating the term…
Abstract
An orthopedic cast made of a mixture of polyethylene and a thermoplastic polyester having a melting point between 50.degree. C. and 100.degree. C., particularly poly (epsilon-caprolactone), having a weight average molecular weight of over 5,000 with a half-time crystallization at 36.degree. C. of between 0.5 minute and 10.0 minutes.
Claims10
An orthopedic cast, comprising a mixture of poly (epsilon-caprolactone) having a formula
- --O--(CH.sub.2).sub.5 --CO--.sub.x
- where x makes the weight average molecular weight greater than 5,000 with polyethylene in an amount in the range from 15% to 30%, the mixture having a softening temperature in the range from 50.degree. C. to 100.degree. C. with a half-time crystallization at 36.degree. C. of between 0.5 minute and 10.0 minutes.
A method of forming an orthopedic cast comprising the steps of:
- (a) forming a preform sheet of a mixture of high density polyethylene with poly (epsilon-caprolactone) of weight average molecular weight greater than 5,000 having a melting point of between 50.degree. C. and 100.degree. C., the polyethylene being present in an amount in the range from 30% to 10% by weight,
- (b) heating the sheet to its softening point,
- (c) forming the sheet into a desired shape, and
- (d) allowing the sheet to cool below its melting point.
1 more element
Method of forming an orthopedic cast, comprising the steps of:
- (a) compounding a mixture of high density polyethylene and polycaprolactone with a cross-linking enhancer and an anti-oxidant in a mixer, the polyethylene being present in an amount in the range from 10% to 30% by weight, the polyethylene and the polycaprolactone having generally similar melt indices,
- (b) forming the mixture into a preform sheet,
- (c) heating the sheet to its softening point, the temperature being maintained in the range between the melting temperature of the polycaprolactone and the melting temperature of the polyethylene to maintain a thixotropic effect,
- (d) forming the sheet into a shape, and
- (e) allowing the sheet to cool below its melting point.
2 more elements
Dependencies are inferred from the claim text.