摘要:
The process and catalyst system disclosed herein comprises the polymerization of a conjugated diene such as 1,3-butadiene in hydrocarbon solution in the presence of a new catalyst composition comprising:(a) a dihydrocarbyl magnesium compound of 1-10 carbon atoms, preferably a dialkyl magnesium having 3-8 carbon atoms in each alkyl group, and(b) an alkali metal compound of the formula R(SM).sub.n, R'.sub.2 NM, R'NHM or RC.tbd.CM, wherein R is a hydrocarbyl radical of 1-10 carbon atoms, preferably alkyl, n is 1, 2 or 3, M is Li, Na or K, and R' is a hydrocarbyl radical of 1-10 carbon atoms or an acyl radical of 1-10 carbon atoms.This process is particularly advantageous in that the polymer product can be controlled to have only a relatively small amount of 1,2 structure in accordance with the polymerization temperature. For example, at 125.degree. C. with Li compounds, the product generally has a 1,2 content of 12.6% or less; at 50.degree. C., 10.6% or less; and at 25.degree. C., 7% or less. Where 1,2 contents of 17-25% are desired, these may be obtained by using the Na compounds, and when 1,2 contents of 37-54% are desired, these may be obtained by using K compounds. Where even higher 1,2 contents are desired, they may be obtained by using an amine, such as tetramethylethylenediamine, as an additional catalyst component.
摘要:
The process and catalyst system disclosed herein comprises the polymerization of a conjugated diene such as 1,3-butadiene in hydrocarbon solution in the presence of a new catalyst composition comprising:(a) a dihydrocarbyl magnesium compound of 1-10 carbon atoms, preferably a dialkyl magnesium having 3-8 carbon atoms in each alkyl group, and(b) an alkali metal compound of the formula R(SM).sub.n, R'.sub.2 NM, R'NHM or RC.tbd.CM, wherein R is a hydrocarbyl radical of 1-10 carbon atoms, preferably alkyl, n is 1, 2 or 3, M is Li, Na or K, and R' is a hydrocarbyl radical of 1-10 carbon atoms or an acyl radical of 1-10 carbon atoms.This process is particularly advantageous in that the polymer product can be controlled to have only a relatively small amount of 1,2 structure in accordance with the polymerization temperature. For example, at 125.degree. C. with Li compounds, the product generally has a 1,2 content of 12.6% or less; at 50.degree. C., 10.6% or less; and at 25.degree. C., 7% or less. Where 1,2 contents of 17-25% are desired, these may be obtained by using the Na compounds, and when 1,2 contents of 37-54% are desired, these may be obtained by using K compounds. Where even higher 1,2 contents are desired, they may be obtained by using an amine, such as tetramethylethylenediamine, as an additional catalyst component.
摘要:
A process and catalyst system is disclosed herein for the preparation of (co)polymers having a 1,2-microstructure of between about 20 and about 65 percent. These (co)polymers are prepared in a hydrocarbon or non-polar solvent from a monomer system which contains at least one 1,3-diene monomer. The catalyst system which is employed in the production of the (co)polymer is a combination of an anionic initiator based on lithium and a phosphine oxide modifier which is substituted with three saturated heterocyclic rings, each hetero ring containing one nitrogen atom and either four, five or six carbon atoms.
摘要:
A process and catalyst system is disclosed herein for the preparation of (co)polymers having a 1,2-microstructure of between about 20 and about 65 percent. These (co)polymers are prepared in a hydrocarbon or non-polar solvent from a monomer system which contains at least one 1,3-diene monomer. The catalyst system which is employed in the production of the (co)polymer is a combination of an anionic initiator based on lithium and a phosphine oxide modifier which is substituted with three saturated heterocyclic rings, each hetero ring containing one nitrogen atom and either four, five or six carbon atoms.
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.