Disclosed are hydrogels polymerized with a biofunctional moiety, biodegradable and permanent, designed to be implantable in a mammalian body and intended to block or mitigate the formation of tissue adhesions. The hydrogels of the present invention are characterized by comprising four structural elements: a) a polymeric backbone which defines the overall polymeric morphology, b) linkage groups, c) side chains, and d) biofunctional end groups. The hydrophobicity of the various structural elements are chosen to reduce tissue adhesion and enhance the biofunctional aspect of the end groups. The morphology of these polymers are typically of high molecular weight and have shape to encourage entanglement. Useful structures include branching chains, comb or brush, and dendritic morphologies.

The invention is directed to biomedical polyurethanes. The invention is particularly directed to biomedical polyurethanes with improved biodegradability and to an improved preparation of the biomedical polyurethanes. In particular the present invention provides a biomedical polyurethane having the formula (A-B-C-B).sub.n, wherein A denotes a polyol, B denotes a diisocyanate moiety, C denotes a diol component and n denotes the number of recurring units, and wherein the B-C-B segment is bioresorbable.

A polylactic acid resin composition, which comprises: a hard segment containing a polylactic acid repeat unit; and a soft segment containing a polyurethane polyol repeat unit in which polyether-based polyol repeat units are linearly connected to each other via a urethane linkage, can be processed at low temperatures and at high rates, has a high solidification rate, and is eco-friendly, due to a low melting point thereof, and thus is useful for 3D printing.

Process for increasingly producing D-Lactide and meso lactide by depolymerizing by back biting polylactide (PLA) said process which comprises: (i) Depolymerizing polylactide into its corresponding dimeric cyclic esters by heating the polylactide in the presence of a catalyst system comprising a catalyst and a co-catalyst in a reaction zone at temperature and pressure at which the polylactide is molten; (ii) Forming a vapor product stream from the reaction zone; (iii) Removing the vapor product stream and optionally condense it; (iv) Recovering, either together or separately meso-lactide, D-lactide and L-lactide.

The present invention relates to a polymer composition comprising a polymeric matrix and particles of an impact modifier within the polymeric matrix, wherein the impact modifier comprises at least one urethane group and the impact modifier is obtainable by reacting in situ within the polymeric matrix a) a polyol comprising a dimer fatty residue; and b) a polyisocyanate. The invention also relates to a method of making the polymer composition.

The present invention relates to biodegradable copolyesters with molecular weight Mn from 10 000 to 100 000 measured by GPC, obtainable via reaction of i) from 51 to 84% by weight, based on the copolyester, of a branched polyester middle block produced from aliphatic or aliphatic and aromatic dicarboxylic acids and from aliphatic dihydroxy compounds with molecular weight Mn from 5000 to 25 000 measured by .sup.1H NMR with from 15.9 to 48.9% by weight, based on the copolyester, of a lactide in the presence of a catalyst, and then the resultant polyester triblock with molecular weight Mn measured by .sup.1H NMR from 5800 to 49 500 with ii) from 0.1 to 3% by weight, based on the copolyester, of a diisocyanate. The present invention further relates to a process for the production of, and to the use of, the abovementioned biodegradable copolyesters.

The present invention relates to a polylactic acid resin composition which has a low glass transition temperature, fusion temperature, and enthalpy of fusion, can be crystallized under commercially meaningful processing conditions, has good film processability such as extrusion properties, has excellent storage stability, and is highly biodegradable. The polylactic acid resin composition comprises a block copolymer comprising a hard segment and a soft segment, the hard segment comprising polylactic acid repeat units, and the soft segment comprising polyurethane polyol repeat units which have polyether-based polyol repeat units linearly connected via a urethane bond, wherein the soft segment is contained by 5% to 35% by weight based on the weight of the block copolymer, and the polylactic acid repeat units include poly(L-lactic acid) repeat units and poly(D-lactic acid) repeat units by a molar ratio of 94:6 to 88:12.

Block copolymers include a poly -methyl--valerolactone (PMVL) block. The PMVL blocks can be formed from biosynthesized -methyl--valerolactone (MVL). The PMVL block may be formed from biosynthesized -methyl--valerolactone (MVL) with a .sup.14C/.sup.12C ratio greater than zero. The block copolymers can include hard blocks. The block copolymers can be thermoplastic elastomers. The block copolymers may include a polylactic acid (PLA) block.

Disclosed are hydrogels polymerized with a biofunctional moiety, biodegradable and permanent, designed to be implantable in a mammalian body and intended to block or mitigate the formation of tissue adhesions. The hydrogels of the present invention are characterized by comprising four structural elements: a) a polymeric backbone which defines the overall polymeric morphology, b) linkage groups, c) side chains, and d) biofunctional end groups. The hydrophobicity of the various structural elements are chosen to reduce tissue adhesion and enhance the biofunctional aspect of the end groups. The morphology of these polymers are typically of high molecular weight and have shape to encourage entanglement. Useful structures include branching chains, comb or brush, and dendritic morphologies.

Provided are oriented biodegradable thermoplastic polyurethane films. The films may be prepared by extruding and drawing biodegradable polyurethane films. The polyurethanes may be prepared from biodegradable polyols and/or biodegradable chain extenders. The films possess high tensile strength yet are degradable under biological conditions. The films may be utilized in the fabrication of devices, particularly implantable medical devices.