Biodegradable polymers with advantageous physical and chemical properties are described, as well as methods for making such polymers. In one embodiment, a new chemical synthesis route to technologically important biodegradable poly(3-hydroxybutyrate) (P3HB) with high isotacticity and molecular weight required for a practical use is described. The new route can utilize racemic eight-membered cyclic diolide (rac-DL), meso-DL, or a rac-DL and meso-DL mixture, derived from bio-sourced dimethyl succinate, and enantiomeric (R,R)-DL and (S,S)-DL, optically resolved by metal-based catalysts. With a stereoselective racemic molecular catalyst, the ROP of rac-DL under ambient conditions produces rapidly P3HB with essentially perfect isotacticity ([mm]>99%), high crystallinity and melting temperature (T.sub.m=171° C.), as well as high molecular weight and low dispersity (M.sub.n=1.54×10.sup.5 g/mol, Ð=1.01).

An organic frame material having zinc containing isopoly-molybdic acid metal, a method of manufacturing the same, and the application thereof are provided. The organic frame material having zinc containing isopoly-molybdic acid metal includes a three-dimensional network structure in which the zinc ions coordinate with 2,3,5,6-tetrafluoro-bis (1,2,4-triazole-1-methyl) benzene ligands and trinuclear molybdate anions. The organic frame material having zinc containing isopoly-molybdic acid metal exhibits high catalytic activity, thermal stability, low toxicity, ease of synthetization and use, and strong reproducibility.

An organic frame material having a cobalt-containing isopoly-molybdic acid metal, a method of manufacturing the same, and applications thereof are provided. The organic frame material having a cobalt-containing isopoly-molybdic acid metal includes a three-dimensional network structure comprising cobalt ions coordinated with 2,3,5,6-tetrafluoro-bis (1,2,4-triazole-1-methyl) benzene ligands and trinuclear molybdate anions. The organic frame material having a cobalt-containing isopoly-molybdic acid metal has higher catalytic activity towards the bulk ring-opening of p-dioxanone. The resulting poly(p-dioxanone) has a weight average molecular weight exceeding 70,000 and is capable of being applied in the field of high polymer materials.

Provided is a copolymer comprising an irregularly arranged structure of a repeating unit of the following Chemical Formula 1 and a repeating unit of the following Chemical Formula 2, and a repeating unit of the following Chemical Formula 3 present at least at one end of the structure:

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and is characterized by having an improved elongation and also having a high weight average molecular weight while maintaining intrinsic properties of a polylactic acid. Also provided are methods of preparing the copolymer.

A method for producing an oligomeric PET substrate for use in a rPET manufacturing process comprises reacting recycled bis-hydroxylethyleneterephthalate (rBHET) or a higher molecular weight oligomer derived from rBHET, with PTA to produce an oligomeric PET substrate represented by Formula (I), wherein R.sub.1 is a carboxyl end group or a hydroxyl end group, R.sub.2 is a carboxyl end group or a hydroxyl end group, and n is a degree of polymerisation.

The invention pertains generally to paints containing a binder curable by an autoxidation mechanism and at least one drier comprising a sulfonate compound of vanadium of formula (VII)

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where R.sup.1 and R.sup.2 are independently selected from a group involving hydrogen, C.sub.1-C.sub.12 alkyl, C.sub.1-C.sub.12 halogenated alkyl, C.sub.6-C.sub.10 aryl, benzyl; and whereas aryl and benzyl can be optionally substituted by up to three substituents independently selected from a group involving C.sub.1-C.sub.20 alkyl, and hydroxy(C.sub.1-C.sub.2)alkyl.

A method for preparing high molecular weight poly(L-lactic acid) with high performance, including: a) providing a biogenic guanidine (BG) as a catalyst, and a nontoxic acid salt of an essential metal trace element as an activator (Act), and adding the catalyst, the activator, and L-lactide monomer to a polymerization reactor; b) evacuating under vacuum and charging the polymerization reactor with nitrogen for three consecutive times to remove air, and allowing the L-lactide monomer to undergo bulk polymerization under vacuum. The bulk polymerization includes a first reaction stage and a second reaction stage, which are separately carried out at different temperatures, pressures, and reaction times.

Provided is a tape including a composition having a copolyester including polymeric units derived from ethylene glycol and terephthalic acid or a diester thereof and >0.50 and <5.00 wt % of polymeric units with regard to the total weight of the polyester derived from an oligomeric dihydroxy compound having a number average molecular weight of >500 g/mol and <5000 g/mol. Such tape has an improved tensile-impact strength and a reduced proneness to splitting during weaving.

An isopoly-molybdic acid coordination polymer catalyst for manufacturing polycaprolactone and method of manufacturing the same are provided. It relates to a field of catalysts from polycaprolactone. The chemical formula of the isopoly-molybdic acid coordination polymer catalyst is [Cu.sub.2(trz).sub.2(γ-Mo.sub.8O.sub.26).sub.0.5(H.sub.2O).sub.2]. In the chemical formula, trz is 1,2,4-triazole negative monovalent anion, and [γ-Mo.sub.8O.sub.26] is a γ type octamolybdate anion. This synthesis method offers higher yield with strong reproducibility. The resulting crystal products have higher purity. The isopoly-molybdic acid coordination polymer catalyst shows high catalytic activity towards the bulk ring-opening polymerization of caprolactone. The resulting polycaprolactone has a weight average molecular weight exceeding 50,000 and a narrow molecular distribution. The polycaprolactone has great potential in the application of low- to medium-temperature thermoplastic medical materials.

An isopoly-vanadic acid coordination polymer catalyst, method of manufacturing the same, and application thereof are provided. The isopoly-vanadic acid coordination polymer catalyst has a chemical formula of [Co(atrz)(V.sub.2O.sub.6)]. The atrz is a 4-amino-1,2,4-triazole ligand, and [V.sub.2O.sub.6] is a binuclear vanadate anion. The isopoly-vanadic acid coordination polymer catalyst shows strong thermal stability, and it is easy to synthesize with high reproducibility. The isopoly-vanadic acid coordination polymer catalyst has a good catalytic activity towards the bulk ring-opening of p-dioxanone. The resulting poly(p-dioxanone) is stable and uniform. The high molecular weight of the resulting poly(p-dioxanone) has great potential in high polymer materials, in particular the field of medical high polymer materials.