摘要:
Compositions including at least one polyamide obtained by polycondensation of meta-xylylenediamine and of a dicarboxylic acid, as well as at least one copolymer based on methyl methacrylate and on acrylic and/or methacrylic acid, the said copolymer being advantageously at least partially neutralized with an alkali metal. These compositions exhibit a high melt viscosity at low shear rate, which facilitates their processing.
摘要:
The present invention relates to microparticles containing an active principle against malaria, such as primaquine, one of its amino acid derivatives, or their conjugates with a hepatotropic vector or their pharmaceutically acceptable salts, and a biocompatible and biodegradable polymer controlling the kinetics of release of the active principle, like (DL)polylactide. The invention also relates to pharmaceutical compositions comprising microcapsules according to the invention. Lastly, the invention relates to processes for the preparation of microparticles as mentioned above, the processes comprising: dissolving the polymer in a volatile solvent, adding to this solution the active principle and possibly a substance regulating the size of the microparticles, and at the end of evaporation, recovering the microparticles by centrifugation and filtration.
摘要:
Prestabilizing copolymers comprising the product of the in situ reaction of a mixture of ethylenically unsatured monomers containing at least one mono-unsaturated monomer containing no groups which can be alkoxylated and one unsaturated monomer containing a group which can be alkoxylated, a prepolyol of low molecular weight and a polymerization catalyst as well as an alkoxylating agent for the abovementioned reaction product chosen from the group comprising ethylene oxide, propylene oxide and their mixtures, process for obtaining dispersions of polymers/polyols and process for obtaining polyurethane foams.
摘要:
A process for the polymerization of acrylic monomers and optionally of vinyl comonomers using (i) an initiator of formula (I):R--M (I)in which M denotes a metal selected from the group consisting of alkali metals and alkaline earth metals and R denotes a straight-chain or branched alkyl radical containing 2 to 6 carbon atoms or an aryl radical, and (ii) at least one non-nitrogenous macrocyclic complexing agent.The polymerization process is used to make products of acrylic polymers having a narrow distribution of molecular masses.
摘要:
The present invention relates to an initiation system composed of the reaction product of at least one cyclic siloxane and at least one organometalic compound of sufficient reactivity to open the siloxane ring. Application of the present invention is to the preparation of homopolymers of (meth)acrylic, vinylaromatic or diene monomers, random or block copolymers of these monomers and, in particular, application to poly(methylmethacrylate) with a high content of isotactic triads.
摘要:
The presently claimed invention comprises a biopolymer nanoparticle for drug delivery wherein the nanoparticle comprises a homogeneous blend of an aliphatic polyester polymer blended with a polyether, a lipophilic or polypeptide drug and a biocompatible cholesterol interacting agent for preserving the activity of the drug administered to the patient while at the same time controlling the release of the drug. Methods for making the homogeneous drug delivery nanoparticles are also disclosed.
摘要:
This process is characterized by the fact that at least one of the said monomers is polymerized or copolymerized in bulk, solution, emulsion or suspension, at a temperature that can be as low as 0.degree. C., in the presence of an initiation system including: at least one compound generating radicals, other than bromofluorene, and at least one catalyst consisting of a complex of palladium in the 0 oxidation state, denoted by the following formula (I): Pd(0)L.sup.1 L.sup.2 L.sup.3 L.sup.4 in which each of L.sup.1, L.sup.2, L.sup.3 and L.sup.4, which are identical or different, denotes a ligand which may be a chiral ligand, which is chosen from PRR'R", P(OR)(OR')(OR"), NRR'R", ORR', SRR', SeRR', AsRR'R", SbRR'R", where each of R, R' and R" independently denotes a C.sub.1 -C.sub.14 alkyl group, optionally substituted, or an optionally substituted aromatic group, it being possible for at least two of these ligands to be joined to one another by one or more divalent radicals.
摘要:
Block copolymers having a first sequence formed with a conjugated diene or a vinyl substituted aromatic hydrocarbon other than alpha-methylstyrene, a second sequence formed with an acrylic ester, and a linking intermediate sequence formed with alpha-methylstyrene. An anionic polymerization process is used to form these block copolymers.
摘要:
The process for the controlled radical (co)polymerization of (meth)acrylic and/or vinyl monomers is characterized in that the bulk, solution, emulsion or suspension polymerization or copolymerization is carried out, at a temperature at which can fall to 0.degree. C., of at least one of the said monomers in the presence of an initiating system comprising a radical-generating compound and at least one catalyst composed of a metal complex containing a ligand of the type�4-R.sup.3 -2,6-(CH.sub.2 NR.sup.1 R.sup.2).sub.2 C.sub.6 H.sub.2 !--(I)in which: R.sup.1 and R.sup.2, which are identical or different, represent a branched or unbranched C.sub.1 -C.sub.4 alkyl group or a phenyl group or alternatively R.sup.1 and R.sup.2 form, with the nitrogen atom to which they are connected, a cyclic amine or alternatively the two R.sup.2 groups, taken together, form a polymethylene bridge and R.sup.3 represents a hydrogen atom, an alkyl or benzyl group or an electron-donating or electron-withdrawing functional group.
摘要:
This process is characterized in that at least one of the said monomers is polymerized or copolymerized in bulk, solution, emulsion or suspension, at a temperature which may be as low as 0.degree. C., in the presence of an initiator system comprising at least one non-peroxy radical-generator compound and at least one catalyst consisting of a metal complex represented by formula Ma.sub.a (L).sub.n in which M represents Rh, Co or Ir; A represents, a halogen or a pseudohalogen; the groups L, which may be identical or different, each represent a ligand which may be a chiral ligand, which is chosen from cyclooctadiene, PRR'R", P(OR) (OR') (OR"), NRR'R", ORR', SRR', SeRR', AsRR'R", SbRR'R", each radical R, R' and R" independently representing an optionally substituted C.sub.1 -C.sub.14 alkyl group or an optionally substituted aromatic group, it being possible for at least two of these ligands to be joined together by one or more divalent radicals; a is an integer such that 1.ltoreq.a.ltoreq.3 ; n is an integer such that 1.ltoreq.n.ltoreq.5, and in the absence of activator.