Expandable thermoplastic polymeric compositions based on styrene polymers
Patent 3991020 Issued on November 9, 1976. Estimated Expiration Date: 
November 9, 1993. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
November 9, 1993. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent References 3468820 3590101 3826765 InventorsAssigneeApplicationNo. 471766 filed on 05/20/1974US Classes:521/57, Including step of surface coating a particle or process of expanding a surface coated particle428/407, Including synthetic resin or polymer521/88, Ingredient is ether, alcohol, or inorganic alcoholate, e.g., phenol, etc.521/91, Ingredient contains a silicon atom521/93, Metal atom is part of an organic compound521/98, Ingredient contains only C and H atoms, only C and halogen atoms, or only C, H, and halogen atoms524/394, Oxygen atom or metal atom DNRM, e.g., metal stearate, etc.524/447, Kaolin or bentonite524/451, Talc (soapstone) DNRM524/577, From aromatic hydrocarbon monomer525/185, With additional solid polymer derived from at least one nonethylenic reactant525/187Heterocyclic ring is an 1,2-epoxy ringExaminersPrimary: Briggs, Sr., Wilbert J.Foreign Application Priority Data1973-05-21 ITAbstractExpandable thermoplastic polymeric compositions based on styrene polymers and copolymers in the form of fine particles are disclosed. The particulate compositions essentially consist of (a) styrene polymers containing one or more expanding agents; (b) a polyether derived from propylene oxide and, optionally also from ethylene oxide, and containing polyhydroxy compounds, the polyether being homogeneously dispersed on the surface and preferably also within the expandable particles and (c) optionally, in combination with powdered inorganic and/or organic substances which are homogeneously dispersed on the surface of the polymer particles. | |
