In a first aspect, the invention relates to a polymer composition comprising (i) a polyester; and (ii) an oxidizable organic polymer consisting of a branched or unbranched alkyl chain, which comprises at least one oxidizable C═C double bond. A second aspect of the invention relates to the use of the polymer composition according to the first aspect for the preparation of a polymer article. In a third aspect, the invention relates to a polymer article comprising the polymer composition according to the first aspect. In a fourth aspect, the invention relates to a method for preparing a polymer composition having oxygen consumption activity.

Techniques regarding the synthesis of one or more polymers through one or more ring-opening polymerizations conducted within a flow reactor and facilitated by one or more anionic catalysts are provided. For example, one or more embodiments can comprise a method, which can comprise polymerizing, via a ring-opening polymerization within a flow reactor, a cyclic monomer in the presence of one or more anionic organocatalysts.

Provided is a triblock copolymer comprising a poly(3-hydroxypropionate) block, and polylactide blocks bonded to both ends of the poly(3-hydroxypropionate) block. Also provided is a method for preparing a triblock copolymer by ring-opening polymerization of lactide monomers in the presence of a poly(3-hydroxypropionate) initiator having hydroxy groups at both ends.

The present disclosure belongs to the field of organic synthesis, and particularly relates to a ring-opening polymerization method for a cyclic monomer. A specific solution is that a Lewis acid-base pair is used to catalyze ring-opening polymerization of the cyclic monomer in the presence of an initiator. By using the Lewis acid-base pair as a catalyst, on one hand, a range of a ring-opening polymerization catalyst is widened, and on the other hand, this catalyst achieves a higher catalytic efficiency and is milder in comparison with previously reported strong acid or strong base catalysts. In addition, through a bifunctional activation mechanism, this catalyst system activates the monomer and simultaneously activates the initiator or a chain end, and has the characteristics of high efficiency in comparison with the reported monomer activation mechanism or chain end activation mechanism. By adopting the catalyst, a polyester product with a target molecular weight can be synthesized in a controlled manner as required, with a narrower molecular weight distribution index, a high product yield, a high product conversion rate and no monomer or metal residues.

This invention relates to the synthesis of multi-block bioresorbable polymers bearing hard and soft polymeric segments. The invention further relates to bioresorbable polymers for shape memory properties. The invention also relates to the use of such polymers as bone filler, vascular closure devices, hemostasis device, aneurysms, mastectomy devices and stent applications. The invention relates also to the use of such polymers for applications in fast degradation applications and 3D printing. The invention also relates to the use of such polymers as drug delivery platforms applications.

A method to prepare a polylactic acid-based polymer; the method comprises: —a mixing step, during which lactide monomers, at least one polymerization catalyst and natural origin reactants are mixed together; —a polymerization step, during which the mixture obtained from the previous mixing step is heated at a temperature ranging from 120 to 220° C. in inert atmosphere; and —a cooling step, during which a polymer mass obtained from said polymerization step is cooled down. The natural origin reactants are: (i) a first compound with general formula (I) wherein n ranges from 1 to 20 (ii) a second compound chosen among citric acid, malic acid and derivatives thereof with the carboxylic groups partially or completely in the form of ester or anhydride and with the hydroxyl groups partially or completely in the form of ester.

##STR00001##

Disclosed herein are catalyst systems useful for a wide range of ring opening polymerization processes. Epoxides, oxetanes, lactones and cyclic carbonates are all suitable substrates for the ring opening polymerization.

Provided is a polyester polyol that can be used for forming a polyurethane excelling in durability and solvent resistance.

A polyester polyol of the present invention is represented by Formula (1) and has a molecular weight distribution of less than 1.2: In Formula (1), R.sup.1 and R.sup.2 represent, identically or differently a divalent hydrocarbon group, and n is an integer. R.sup.3 to R.sup.7 represent, identically or differently a hydrogen atom, a monovalent hydrocarbon group, or a group represented by Formula (2): In Formula (2), m and s represent, identically or differently an integer of 1 or greater. 2m occurrences of R.sup.8 represent, identically or differently a hydrogen atom, an alkyl group, or an alkoxy group. Note that at least two of the groups represented by R.sup.3 to R.sup.7 are represented by Formula (2):

##STR00001##

Provided is a liquid crystal polyester powder including a liquid crystal polyester having a number average molecular weight of 10000 or less, in which an average particle diameter of the liquid crystal polyester powder is 0.5 to 20 μm.

Provided is a liquid crystal polyester powder including a liquid crystal polyester having a number average molecular weight of 10000 or less, in which an average particle diameter of the liquid crystal polyester powder is 0.5 to 20 μm.