Abstract:
The invention is directed to a process for preparing a polyester or copolymer containing ester functionalities, and more in particular to a process for preparing a polyester or copolymer containing ester functionalities using metal mediated ring-opening polymerization. The process of the invention comprises providing an optionally substituted lactone having a ring size of from 6 to 40 carbon atoms; and subjecting said lactone to metal mediated ring-opening polymerization using as catalyst a compound according to general formula (I) wherein - M is selected from the group consisting of A1, Cr, Mn and Co; - X and X' are independently a heteroatom; - Y and Y' are independently selected from the group consisting of O, N, S, P, C, Si, and B; - Z is selected from the group consisting of selected from the group consisting of hydrogen, borohydrides, aluminum hydrides, carbyls, silyls, hydroxide, alkoxides, aryloxides, carboxylates, carbonates, carbamates, amidos, thiolates, phosphides, and halides; - L 1 and L 2 are independently an organic ligand linking X and Y together and linking X' and Y' together, respectively; and - L 3 is an optional organic ligand linking Y and Y' together.
Abstract:
The invention deals with oligomerization, especially tetramerization of olefins by use of a catalyst system comprising an organometalliccomplex of an element of group 3 to 10 of the Periodic Table of the Elements and a didendate nitogen comprising ligand.
Abstract:
Process for the production of a polyester by the polycondensation of a mixture comprising isoidide, and a dicarboxylic acid or dicarboxylic acid anhydride, wherein the reaction is performed in the melt of the monomers and wherein these monomers are not activated. The polyesters based on one or more of the three isomers of dianhydrohexitol, being isosorbide, isomannide and isoidide, have properties which makes them suitable to be used in powder coatings, toner compositions as well as engineering plastics. The polyesters include a polyester according to the following formula, wherein n ranges from 3 to 300.
Abstract:
Transition metal compound comprising at least one ligand system L with a nitrogen-phosphorus-nitrogen-structural element wherein phosphorus is pentavalent, catalyst system for the oligomerization of olefins comprising such a transition metal complex and process for oligomerization of olefinic monomers carried out in the presence of the catalyst system.
Abstract:
The invention deals with oligomerization, especially tetramerization of olefins by use of a catalyst system comprising an organometalliccomplex of an element of group 3 to 10 of the Periodic Table of the Elements and a didendate nitogen comprising ligand.
Abstract:
The invention relates to polycarbonate containing a dianhydrohexitol residue, obtainable from a polysaccharide, and a polyol residue, wherein the polycarbonate comprises between 0.2 and 5 mmol hydroxyl groups per gram polymer. The polycarbonate may be branched and comprises functional groups that can react with suitable crosslinkers. The polycarbonate can be used in for example coating compositions.
Abstract:
The invention relates to a process for the manufacture of a shaped part of ultra high molecular weight polyethylene (UHMWPE) comprising melt processing, wherein a) the UHMWPE has a weight average molecular weight (Mw) of at least 1 * 10 6 g/mol, b) during the shaping the storage plateau modulus of the UHMWPE (G*) is kept at a value of at most 1.5 MPa, c) whereafter, before the cooling, the G* is raised to its final value. The invention further relates to a shaped part obtainable with the process and the use of the shaped part in a medical application.
Abstract translation:本发明涉及制造包含熔体加工的超高分子量聚乙烯(UHMWPE)成形部件的方法,其中a)UHMWPE的重均分子量(Mw)至少为1×10 6 g / mol,b)在成型期间,UHMWPE(G *)的储存平台模量保持在至多1.5MPa的值,c)之后,在冷却之前,将G *升高到其最终值。 本发明还涉及可以通过在医疗应用中的成形部件的工艺和使用而获得的成形部件。
Abstract:
Transition metal compound comprising at least one ligand system L with a nitrogen-phosphorus-nitrogen-structural element wherein phosphorus is pentavalent, catalyst system for the oligomerization of olefins comprising such a transition metal complex and process for oligomerization of olefinic monomers carried out in the presence of the catalyst system.
Abstract:
characterized in that the polymerization is carried out in a single step in the presence of a chain transfer agent.Preferred chain transfer agents are polyols. The invention also relates to branched polycarbonates that havefunctional hydroxyl endgroups.