Novel composite materials comprising a thermoplastic matrix polymer and wood particles

Abstract

The present invention concerns a novel low-temperature thermoplastic wood-biopolymer composite comprised of small wood particles and a polycaprolactone (PCL) homopolymer for use in medical procedures including orthopedic casting or splinting. The material is made from a thermoplastic composite that softens when heated to approximately 60° C., after which it can be formed directly on the patient. The composite then retains its shape as it cools down. The material is composed of epsilon caprolactone homopolymer reinforced with discontinuous short length wood particles.

What is claimed is: 
     
         1 . A sports orthosis device comprising:
 a composite material including:   a first component formed by a biodegradable thermoplastic polymer, and   a second component formed by a reinforcing material, the second component including granular or plate-like wood particles.   
     
     
         2 . A sports orthosis device according to  claim 1 , wherein the device is a shin pad. 
     
     
         3 . The sports orthosis device according to  claim 1 , wherein the composite material comprises:
 5 to 99 parts by weight of a thermoplastic polymer component; and   1 to 95 parts by weight of the wood particles, the weight of the wood particles being calculated based on the dry weight of said wood particles.   
     
     
         4 . The sports orthosis device according to  claim 3 , wherein the composite material comprises:
 40 to 99 parts by weight of a thermoplastic polymer component; and   1 to 60 parts by weight of the wood particles, the weight of the wood particles being calculated based on the dry weight of said wood particles.   
     
     
         5 . A foot-supporting device comprising:
 a composite material including:   a first component formed by a biodegradable thermoplastic polymer, and   a second component formed by a reinforcing material, the second component including granular or plate-like wood particles.   
     
     
         6 . A foot-supporting device according to  claim 5 , wherein the device is an insole. 
     
     
         7 . The foot-supporting device according to  claim 5 , wherein the composite material comprises:
 5 to 99 parts by weight of a thermoplastic polymer component; and   1 to 95 parts by weight of the wood particles, the weight of the wood particles being calculated based on the dry weight of said wood particles.   
     
     
         8 . The foot-supporting device according to  claim 7 , wherein the composite material comprises:
 40 to 99 parts by weight of a thermoplastic polymer component; and   1 to 60 parts by weight of the wood particles, the weight of the wood particles being calculated based on the dry weight of said wood particles.   
     
     
         9 . A shin pad comprising:
 a composite material including:   a first component formed by a biodegradable thermoplastic polymer, and   a second component formed by a reinforcing material, the second component including granular or plate-like wood particles.   
     
     
         10 . The shin pad according to  claim 1 , wherein the composite material comprises:
 5 to 99 parts by weight of a thermoplastic polymer component; and   1 to 95 parts by weight of the wood particles, the weight of the wood particles being calculated based on the dry weight of said wood particles.   
     
     
         11 . The shin pad according to  claim 10 , wherein the composite material comprises:
 40 to 99 parts by weight of a thermoplastic polymer component; and   1 to 60 parts by weight of the wood particles, the weight of the wood particles being calculated based on the dry weight of said wood particles.   
     
     
         12 . The sports orthosis device according to  claim 1 , wherein the thermoplastic polymer is selected from the group consisting of epsilon-caprolactone homopolymers, blends of epsilon-caprolactone homopolymers and other biodegradable thermoplastic homopolymers, with 5-99 wt % of an epsilon-caprolactone homopolymer and 1-95 wt % of a biodegradable thermoplastic polymer, and copolymers of epsilon-caprolactone homopolymer and any thermoplastic biodegradable polymer, with 5 to 99 wt % of repeating units derived from epsilon-caprolactone and 1 to 95 wt % repeating units derived from other polymerisable material. 
     
     
         13 . The sports orthosis device according to  claim 12 , wherein the thermoplastic polymer is selected from the group consisting of epsilon-caprolactone homopolymers, blends of epsilon-caprolactone homopolymers and other biodegradable thermoplastic homopolymers, with 40-99 wt % of an epsilon-caprolactone homopolymer and 1-60 wt % of a biodegradable thermoplastic polymer, and copolymers of epsilon-caprolactone homopolymer and any thermoplastic biodegradable polymer, with 40 to 99 wt % of repeating units derived from epsilon-caprolactone and 1 to 60 wt % repeating units derived from other polymerisable material. 
     
     
         14 . The sports orthosis device according to  claim 1 , wherein the thermoplastic polymer has an average molecular weight of about 60,000 to 500,000 g/mol. 
     
     
         15 . The sports orthosis device according to  claim 1 , wherein the thermoplastic polymer has an inherent viscosity in the range of about 1.5 to 2.5 dl/g. 
     
     
         16 . The sports orthosis device according to  claim 1 , wherein the wood particles have an average size (of the smallest dimension) of at least 0.5 mm. 
     
     
         17 . The sports orthosis device according to  claim 1 , wherein the wood particles have an average size (of the smallest dimension) of between 1 to 40 mm. 
     
     
         18 . The sports orthosis device according to  claim 1 , wherein the wood particles have at least two dimensions greater than 1 mm and one greater than 0.1 mm, said wood particles having an average volume of at least 1 mm 3 . 
     
     
         19 . The sports orthosis device according to  claim 1 , wherein the wood particles are plate-like and have a ratio of the thickness of the plate to the smaller of the width or length of 1:2 to 1:50.