摘要:
A biodegradable cationic polymer is disclosed, comprising first repeat units derived from a first cyclic carbonyl monomer by ring-opening polymerization, wherein more than 0% of the first repeat units comprise a side chain moiety comprising a quaternary amine group; a subunit derived from a monomeric diol initiator for the ring-opening polymerization; and an optional endcap group. The biodegradable cationic polymers have low cytotoxicity and form complexes with biologically active materials useful in gene therapeutics and drug delivery.
摘要:
The present application is directed to a method for preparing a cyclic carbonate functional polyester, said method comprising: reacting glycerine carbonate with an anhydride to form an Adduct (A); and, reacting said Adduct (A) with at least one polyepoxide compound to form said cyclic carbonate functional polyester (CC-PES). More particularly, the present application is directed to a method for preparing a cyclic carbonate functional polyester, said method comprising the stages: A) reacting glycerine carbonate with an anhydride to form an Adduct (A); B) providing a polycarboxylic acid; C) reacting said polycarboxylic acid with at least one diglycidyl ether to form an epoxy functional polyester; and, D) reacting said epoxy functional polyester with said Adduct (A) to form said cyclic carbonate functional polyester.
摘要:
The invention relates to the synthesis and process thereof of a Quorum Sensing (QS) based polymer formed by the process of ring opening polymerization/ring opening copolymerization. The formed homopolymer or heteropolymer or copolymer displays increased half-life, bioactivity and biostability in stimulating the microbial quorum sensing in a predetermined microbial population.
摘要:
Disclosed are new classes of diphenol compounds, derived from tyrosol or tyrosol analogues and hydroxybenzoic acid, which are useful as monomers for preparation of biocompatible polymers. Also disclosed are biocompatible polymers prepared from these monomeric diphenol compounds, including novel biodegradable and/or bioresorbable polymers of formula. These biocompatible polymers or polymer compositions with enhanced bioresorbabilty and processibility are useful in a variety of medical applications, such as in medical devices and controlled-release therapeutic compositions. The invention also provides methods for preparing these monomeric diphenol compounds and biocompatible polymers.
摘要:
Disclosed is a copolycarbonate including aromatic polycarbonate-based repeating units represented by Chemical Formula 1 and Chemical Formula 2; and aromatic polycarbonate-based repeating units having siloxane bonds represented by Chemical Formula 3 and Chemical Formula 4: copolycarbonate provides improved impact strength at low-temperature, improved YI (yellow index), and improved melt index simultaneously.
摘要:
A method can include immortal ring-opening homopolymerisation of cyclic carbonates or cyclic esters in the presence of a catalytic system, or sequential two-step ring-opening block copolymerisation of one or more cyclic monomers selected from cyclic carbonates or cyclic esters in the presence of the catalytic system. The catalytic system can include a phenolate supported metallic complex. The catalytic system can also include an alcohol or a primary amine containing aliphatic and/or aromatic moieties. The alcohol or primary amine can be present in a molar ratio with respect to the metallic complex that is larger than 1.
摘要:
The invention relates to a process for the preparation of polycarbonate polyols, characterized in that cyclic carbonates are polymerized in the presence of DMC catalysts and chain-transfer agents consisting of polyether carbonate polyols.
摘要:
A method for recovering a dihydroxy aromatic compound and urea from a polycarbonate-containing composition comprising a polycarbonate and a phosphorus-containing flame retardant, comprising contacting the composition with ammonia in the presence of a swelling solvent for a time sufficient to depolymerize the polycarbonate producing a dihydroxy aromatic compound and urea.
摘要:
The present invention relates to a biodegradable thermoplastic elastomer having the general formula A-B-A wherein each A is an amorphous polymer having a glass transition temperature (Tg)>40° C. or a semi-crystalline polymer having a glass transition temperature (Tg) and/or melting temperature (Tm)>40° C.; B is a copolymer of -caprolactone (CL) and at least one additional monomer selected from the group consisting of L-lactic acid (LLA), trimethyl carbonate (TMC), and glycolic acid (GA), or B is different to A and is lactic-co-glycolic acid (LGA); and wherein the molar ratio of CL to the at least one additional monomer in the copolymer B is in the range between about 1:0.09 to about 1:1.
摘要:
A method of preparing a polymerizate from a reactant monomer of prepolymer which undergoes shrinkage during the formation of said polymerizate which comprises reacting said reactant monomer or prepolymer in the presence of a monomer selected from the group consisting of: ##STR1## wherein R.sub.1 -R.sub.8 are as defined herein to form a polymerizate containgin said reactant monomer or prepolymer as chemically contained constituents thereof, and resinous compositions and composites as well as polymers polymerized from such monomers or prepolymers.