RECYCLED THERMOPLASTIC COMPOSITION
Publication Date: 2005-Mar-14
The IP.com Prior Art Database
A thermoplastic composition comprises: a desired recovered thermoplastic selected from the group consisting of polycarbonate, polycarbonate/acrylonitrile-butadiene-styrene graft copolymer blends, polycarbonate/polyester blends and combinations of the foregoing; less than or equal to about 0.1 weight percent based on the total weight of the composition of an extremely undesirable recovered thermoplastics selected from the group consisting of polyvinyl chloride, polyoxymethylene, polyurethane, acrylonitrile-butadiene-styrene graft copolymer, polyamide, polyester, poly(arylene ether) and combinations of two or more of the foregoing; about 0.025 to about 4.0 weight percent based on the total weight of the composition of one or more of undesirable or highly undesirable recovered thermoplastics selected from the group consisting of polyolefin, polymethyl methacrylate, and poly(alkenyl aromatic) polymer, wherein combinations of two or more of the foregoing undesirable and/or highly undesirable recovered thermoplastics are present in an amount less than or equal to about 10 weight percent, based on the total weight of the composition; and a virgin thermoplastic.
RECYCLED THERMOPLASTIC COMPOSITION
BACKGROUND OF INVENTION
 The disclosure relates to recycled thermoplastic compositions.
 Thermoplastics are increasingly important as materials useful in the manufacture of a wide variety of items. It has long been acknowledged that the recycling of thermoplastics is highly desirable to decrease the waste stream and conserve precious natural resources. The recycling of thermoplastics has been a challenging endeavor due, in part, to the wide variety of thermoplastics in use and the difficulty in separating them. As a result recycled thermoplastics are frequently contaminated with other thermoplastics in levels such that the recycled thermoplastic is suitable for use in a narrower range of applications than virgin thermoplastic. This is further complicated by the fact that within a single type of thermoplastic there may be a wide range of grades and types with significant variability in physical properties. Additionally, the commingling of some thermoplastics, which would be compatible by themselves, is unsuccessful due to the presence of additives. A classic example of this would be the “ incompatibility “ of ABS with PC/ABS blends. At first glance, this would seem impossible, since ABS is a component of PC/ABS blends. However, to one skilled in the art of both of these systems, the answer becomes apparent. Additives used in ABS may be incompatible with PC. Since additives to achieve a specific effect for PC are much more expensive than other classes of additives used in ABS, there is an economic incentive for ABS manufacturers to use additives that are not compatible with PC.
 One approach to this problem has been to limit the recycle material to a small segment of available material in a way that allows only a very limited variability in the composition of the recycle stream. Examples of this would be the recycling of compact discs or five-gallon water bottles, made of polycarbonate. Another approach has been to provide commingled products that have limited performance profiles. These products would be limited to applications that have very low demands on the material. These approaches have significant limitations, either in feed streams that are available, or outlets for low performance profile recycle blends.
 Accordingly, there is a need for a thermoplastic composition comprising recycled thermoplastic that can be used in a wider range of applications.
Brief Description of the Invention
 The above described need is addressed by a thermoplastic composition comprising:
a first recovered thermoplastic selected from the group consisting of polycarbonate, polycarbonate/acrylonitrile-butadiene-styrene graft copolymer (PC/ABS) blends, and polycarbonate/polyester blends;
less than or equal to about 0.1 weight percent based on the total weight of the composition of a second recovered thermoplastic selected from the group consisting of polyvinyl chl...