摘要:
Blends of polyarylene ether resins and anionically-polymerized monovinylidene aromatic compounds having a molecular weight distribution not greater than 1.8 are characterized by a lowered melt viscosity without significant loss in mechanical properties. The incorporation of elastomeric toughening agents does not significantly negatively affect processability or other properties of the blends.
摘要:
Blends of polyarylene ether resins and anionically-polymerized monovinylidene aromatic compounds having a molecular weight distribution not greater than 1.8 are characterized by a lowered melt viscosity without significant loss in mechanical properties. The incorporation of elastomeric toughening agents does not significantly negatively affect processability or other properties of the blends.
摘要:
The specification discloses a monovinylidene aromatic polymer having a molecular weight of at least 50,000 and an extremely narrow molecular weight distribution of less than 1.5, preferably with at least 80% by weight of the polymer having a molecular weight within plus or minus 30% of the weight average molecular weight. This polymer is produced through anionic polymerization of a pure feed stock which is first cooled to a temperature at which an anionic initiator preferentially reacts with impurities present in the feed stock and initiates the polymerization reaction but does not substantially propagate styrene polymerization. The initiator is uniformly dispersed into the feed stock while maintaining it at the lower temperature and the feed stock temperature is subsequently increased to a temperature at which polymerization of the sytrene proceeds normally. The resulting polymer is especially well adapted to injection molding in that exceptional strength properties are achieved in combination with good processability, e.g., melt flow rate.
摘要:
An impact resistant polymeric composition and a process for its production. The composition comprises a rigid polymeric matrix comprising an anionically polymerized copolymer of at least one isopropenyl aromatic monomer and at least one vinyl aromatic monomer, said matrix having dispersed therein an elastomeric phase comprising at least one moderately cross-linked ungrafted rubber and at least one moderately cross-linked lightly-grafted rubber, wherein the lightly-grafted rubber has a graft-to-rubber ratio of 0.9:1 or less. The elastomeric phase is melt agglomerated to provide aggregates having particle sizes in the range from 3,000 to 100,000.
摘要:
An impact resistant thermoplastic polymer comprising highly occluded rubbery particles is prepared by contacting an emulsion of a rubbery polymer with at least one addition polymerizable, graftable monomer under conditions such that the rubber emulsion particles imbibe the monomer, but substantially no monomer polymerization occurs followed by free radically polymerizing the monomer and thereafter repeating steps (a) and (b) at least one more time.
摘要:
A method for the treatment of a person suffering from neurodegenerative disease such as Alzheimer's, Parkinson's, or Huntington's disease by treating the patient's brain, over the span of one year or less with a plurality of doses of ionizing radiation, each dose being more than 2.5 mJ/kg but less than 150 mJ/kg with the total dose being more than 10 mJ/kg but less than 400 mJ/kg.
摘要:
The instant invention is the storage of Type II collagen containing tissue in carbonated water. Such Type II collagen is useful for alleviating the symptoms of arthritis in mammals as well as the treatment of arthritis in mammals. Such Type II collagen is also useful for the prevention of arthritis in mammals. The instant invention is also a method for the preparation of a nutritional supplement that includes the steps of: (a) separating water-insoluble undenatured Type II collagen containing animal tissue from animal tissue not containing Type II collagen; (b) subdividing and sterilizing said tissue under conditions which do not change the original structure of the Type II collagen to produce a subdivided and sterilized product; (c) packaging the subdivided and sterilized product in carbonated water.
摘要:
A method for adding intact fiber reinforcing material into thermoplastic resin compositions for toughening purposes without breakage of the fibers, including blending a polymeric solution and chopped fibers in a mixture at low to medium shear, injecting the resulting mixture into an extruder with a resin to be reinforced at an entry point positioned very near a vacuum point, and then removing the solvent for recycle while the reinforcing glass fiber and polymer blend is extruded.
摘要:
This invention relates to an improved method for forming a grafted rubbery particle suitable for use as a reinforcing rubber in a thermoplastic resin. The grafted rubbery particles produced by the method of the present invention have a substantially continuous, generally uniform layer of polymer grafted to the rubber particle core.
摘要:
Alkali metal salicylate can be efficiently acidified and the salicylic acid product formed contemporaneously sublimed by contacting the salicylate as a solid with gaseous hydrogen chloride at the conditions specified. The temperature of the gaseous hydrogen chloride is controlled so that the heat required to sublime the salicylic acid product is predominantly supplied by the heat of reaction of the hydrogen chloride with the alkali metal salt of the carboxylic acid.