摘要:
A process is provided for the preparation of tapered copolymers by the nonaqueous dispersion polymerization of a mixture of 30 to 70% by weight of a conjugated diolefin monomer, preferably butadiene, and 30 to 70% by weight of a vinyl substituted aromatic monomer, preferably styrene, in a liquid hydrocarbon dispersion medium with an anionic initiator catalyst system in the presence of a block copolymeric dispersing agent. At least one block of the dispersing agent is prepared prior to the dispersion polymerization reaction and at least one block of the dispersing agent is prepared in situ during the dispersion copolymerization. The block of the dispersing agent that is prepared in situ has the polymer structure of the tapered copolymer.
摘要:
The present invention relates to a process for the dispersion copolymerization of 35 to 70% by weight of vinyl substituted aromatic monomer and 30 to 65% by weight of conjugated diene monomer comprising carrying out the copolymerization in a reaction mixture containing a liquid aliphatic hydrocarbon dispersing medium, an anionic catalyst system, and an "A" block of a copolymer dispersing agent, the dispersing agent having at least two polymer blocks wherein at least one of the polymer blocks is soluble in the dispersing medium and at least another of the polymer blocks is insoluble in the dispersing medium and is formed in situ.
摘要:
A process is discontinuously preparing continuously tapered SBR-type copolymers optionally having a continuous change in microstructure along the polymer. The process produces tapered block copolymers with multiple glass transition temperatures of very small energy absorption, i.e. no definable glass transition temperature.
摘要:
Terminally functionalized polymers that are living or pseudo-living polymers reacted with certain allyl glycidyl ethers, or certain allylhalosilanes or combinations thereof, and a process for preparing the terminally functionalized polymers. Rubber-modified polymeric compositions comprising the terminally functionalized polymers.
摘要:
A polymer nanoparticle is provided. The nanoparticle includes an inner layer having alkenylbenzene monomer units. The nanoparticle further includes an outer layer having monomer units selected from conjugated dienes, alkylenes, alkenylbenzenes, and mixtures thereof. The nanoparticle has at least one functional group associated with the outer layer. Applications of use as additives for rubber, including the rubber compositions, are also provided.
摘要:
Provided is a method comprising reacting the anionic living end of a polymer with a compound selected from the group consisting of tin halides and silicon halides to produced a polymer with a homolytically cleavable group containing a Sn—C bond or a Si—C bond. An engineered plastic may then be produced by adding the polymer containing a homolytically cleavable group containing a Sn—C bond or a Si—C bond to a solvent comprising at least one vinyl monomer; (b) optionally adding at least one additional inert solvent; (c) optionally adding additives selected from the group consisting of extender oils, modifiers, and antioxidants; and (d) initiating polymerization of the at least one vinyl monomer by the use of an initiator and/or heat, wherein a free radical is produced from the polymer containing a homolytically cleavable group containing a Sn—C bond or a Si—C bond.
摘要:
Provided is a method comprising reacting the anionic living end of a polymer that is end capped with a steric hindering compound with a carbonyl-containing compound to produce a polymer with a homolytically cleaveable group. An engineered plastic may then be produced by adding the polymer containing a homolytically cleavable group to a solvent comprising at least one vinyl monomer; (b) optionally adding at least one additional inert solvent; (c) optionally adding additives selected from the group consisting of extender oils, modifiers, and antioxidants; and (d) initiating polymerization of the at least one vinyl monomer by the use of an initiator and/or heat, wherein a free radical is produced from the polymer containing a homolytically cleavable group.
摘要:
A method of treating Pneumocystis carinii pneumonia in a subject in need of such treatment is disclosed. The method comprises orally administering to the subject a bis-benzamidoxime, or a pharmaceutically acceptable salt thereof, that is reduced in the subject to produce a benzamidine having anti-P. carinii activity. The method of the present invention may alternatively comprise intravenously administering to the subject an active compound as disclosed herein. Pharmaceutical formulations and active compounds useful in the practice of the present invention are also disclosed.
摘要:
The instant invention teaches a method for enabling the formation of a high damping, soft polymer gel. The method includes: reacting a poly(maleimide-co-alkenyl benzene) polymer with a nylon and an alkyl diamine under substantially dry conditions sufficient to form a nylon grafted poly(maleimide-co-alkenyl benzene) polymer product; and, dispersing the nylon grafted poly(maleimide-co-alkenyl benzene) polymer product with an extender oil sufficient to form the gel. The instant invention also contemplates a polymer gel composition, a polymer composition and an article manufactured from the polymer gel composition.
摘要:
The present invention provides methods for treating Pneumocystis carinii pneumonia in a subject in need of such treatment. The methods comprise administering to a subject in need thereof, a pyrimidine of Formula I. ##STR1## wherein the variables are as defined in the specification.