MOLDING THERMOPLASTIC INJECTION-MOLDED AND FLUSHABLE MATERIALS

• Main Authors: Shlepr, Michael G, Mleziva, Mark M, DeMarco, Alphonse, Woltman, Garry R, Wideman, Gregory J, Pickett, Austin N, Lortscher, Peter S
• Format: Patent
• Language: English
• Published: 05.12.2019
• Subjects: AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING; BANDAGES, DRESSINGS OR ABSORBENT PADS; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF,TUBULAR STRUCTURES OF THE BODY, E.G. STENTS; FILTERS IMPLANTABLE INTO BLOOD VESSELS; FIRST-AID KITS; FOMENTATION; HUMAN NECESSITIES; HYGIENE; MEDICAL OR VETERINARY SCIENCE; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; PERFORMING OPERATIONS; PROSTHESES; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDEDFOR; SHAPING OR JOINING OF PLASTICS; TRANSPORTING; TREATMENT OR PROTECTION OF EYES OR EARS; WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE, IN GENERAL

A method for forming an injection-molded part includes applying a coating to a mold cavity; maintaining a water-dispersible, thermoplastic composition at a temperature between 170° C. and 190° C., wherein the thermoplastic composition comprises partially-hydrolyzed polyvinyl alcohol (PVOH), polyethylene glycol (PEG), plasticizer, and a hydrophobic polymeric component, wherein the composition has a melt flow rate of from 40 grams per 10 minutes to 160 grams per 10 minutes when subjected to a load of 2160 grams at a temperature of 190° C. according to ASTM Test Method D1238-E; injecting the thermoplastic composition into the mold cavity; shaping the thermoplastic composition into a molded part within the mold cavity; and maintaining the mold temperature at less than 20° C.