摘要:
Copolymers of tetrafluoroethylene (TFE) and hexafluoropropylene (HFP) having high HFP content and end-of-melting temperature, T.sub.m (end), as low as 200.degree. C. are disclosed. Exceptional performance as a processing aid in polyolefins results from having T.sub.m (end) of the TFE/HFP copolymer close to the processing temperature of the polyolefin. These TFE/HFP copolymers are soluble in fluorinated cyclic solvents. Copolymer/solvent systems copolymer at significant concentrations in selected solvents are fluid and stable at room temperature.
摘要:
Extruded shaped structures of amorphous polyarylate copolymers, having a tensile elongation at break of at least 80% at 25.degree. C., are made by drawing a molten extrudate of the copolymer at a temperature at least 100.degree. C. above the glass transition temperature of the copolymer.
摘要:
Extruded shaped structures of amorphous polyarylate copolymers, having a tensile elongation at break of at least 80% at 25.degree. C., are made by drawing a molten extrudate of the copolymer at a temperature at least 100.degree. C. above the glass transition temperature of the copolymer.
摘要:
Polymer blend composition having improved processibility and comprising:(a) a major portion of a difficultly melt-procesible polymer, and(b) a minor portion of:1 at least an effective amount, to improve processibility, of a fluorocarbon copolymer which at the melt-processing temperature of (a) is either in a melted form if crystalline, or is above its glass transition temperature if amorphous, and(2) at least an effective amount, to improve processibility, of at least one tetrafluoroethylene homopolymer or copolymer of tetrafluoroethylene and at least one monomer copolymerizable therewith, wherein the mole ratio of fluorine to hydrogen is at least 1:1, and which is solid at the melt-processing temperature of (a);masterbatches comprised of the processing aid; and processes utilizing the processing aid.
摘要:
It has now been discovered that a selected magnesium oxychloride can be mixed with a thermoplastic polymer sensitive to decomposition by water, such as polyamides or polyesters, or with fluoropolymers.
摘要:
An elastomeric composition comprising an elastomer matrix having dispersed therein about 3-30 parts per 100 parts by weight of the elastomer of powdered polytetrafluoroethylene having a number average molecular weight of at least about 250,000 and a surface area of at least 1 m.sup.2 /g which has been treated with about 50-120% of sodium-naphthalene addition compound or another addition compound of an alkali metal required for the alkali metal to react with all the fluorine atoms on the surface of the polytetrafluoroethylene powder.By dispersing such treated polytetrafluoroethylene powder in elastomer matrix, one increases significantly the tear strength of the elastomer, while increasing its modulus only moderately. In this way, the processability of the elastomeric compositions is not adversely affected.
摘要:
Core/shell fluoropolymer compositions in particulate form, wherein the core is a highly crystalline polymer such as, for example, tetrafluoroethylene, and the shell is an elastomeric fluoropolymer such as, for example, a vinylidene fluoride/hexafluoropropene copolymer, optionally also containing a cure site monomer are outstanding additives for uncured fluoroelastomer compositions, which after curing in the presence of dispersed core/shell fluoropolymers have improved tear strength, tear strength to modulus ratio, and certain other physical properties.