A series of di‐ and triblock copolymers [poly(L‐lactide‐b‐ε‐caprolactone), poly(D,L‐lactide‐b‐ε‐caprolactone), poly(ε‐caprolactone‐b‐L‐lactide), and poly(ε‐caprolactone‐b‐L‐lactide‐b‐ε‐caprolactone)] have been synthesized successfully by sequential ring‐opening polymerization of ε‐caprolactone (ε‐CL) and lactide (LA) either by initiating PCL block growth with living PLA chain end or vice versa using titanium complexes supported by aminodiol ligands as initiators. Poly(trimethylene carbonate‐b‐ε‐caprolactone) was also prepared. A series of random copolymers with different comonomer composition were also synthesized in solution and bulk of ε‐CL and D,L‐lactide. The chemical composition and microstructure of the copolymers suggest a random distribution with short average sequence length of both the LA and ε‐CL. Transesterification reactions played a key role in the redistribution of monomer sequence and the chain microstructures. Differential scanning calorimetry analysis of the copolymer also evidenced the random structure of the copolymer with a unique Tg. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012

The melt polymerization of diglycerol with bicyclic anhydride monomers derived from a naturally occurring monoterpene provides an avenue for polyesters with a high degree of sustainability. The hydrophobic anhydrides are synthesized at ambient temperature via a solvent-free Diels-Alder reaction of α-phellandrene with maleic anhydride. Subsequent melt polymerizations with tetra-functional diglycerol are effective under a range of [diglycerol]/[anhydride] ratios. The hydrophobicity of α-phellandrene directly impacts the swelling behavior of the resulting polyesters. The low E factors (<2), large amount of bio-based content (>75%), ambient temperature monomer synthesis, and polymer degradability represent key factors in the design of these sustainable polyesters.

Partition coefficients (LogP) help to quantify hydrophobicity, which can be used to guide the design of polymer electrolytes with targeted properties. Thus, this study combined synthetic experiments and molecular modeling to produce polyester electrolytes that solubilize lithium salts. These polyester electrolytes were derived from natural sources and polymerized with different ratios of polyols (diglycerol, glycerol, and diethylene glycol) and citric acid in the presence of lithium salts (LiTf and LiTFSI). The Fisher esterification produced homogeneous, cross-linked films with high optical transparency, whereas the lithium salts increased glass transition temperatures. The LogP values of monomers and the resulting polyesters were predicted using cheminformatics tools and indicate changing diglycerol to glycerol or diethylene glycol alters the hydrophobicity. Comparison of different molecular modeling methods with predicted LogP values demonstrate that LogP values are a reliable means of tailoring physical and chemical properties of these polymer electrolytes. Additionally, LogP values greatly benefit from being extremely less expensive from a computational standpoint as well as more convenient for calculating precursory quantitative information.

Continuous flow methodology for the multi step synthesis of biomass derived aliphatic bicyclic-anhydride monomer. Polymerization with bio-based alcohols results in renewable polyesters with good thermal stability.

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Several titanium complexes based on aminodiol ligands were tested as initiators for the ring-opening polymerization (ROP) of e-caprolactone under solution and bulk conditions. All complexes were found to be efficient under both conditions. For bulk polymerization at 70 C, high activities were observed (113.3-156.2 g poly mmol cat À1 h À1 ) together with controlled molar mass distribution. Kinetic studies revealed controlled polymerization, and the chain propagation was first order with respect to monomer conversion. One complex was also tested for the ROP of rac-b-butyrolactone and the end-group analysis suggested that ring opening occurs through acyl-oxy-gen bond cleavage via coordination-insertion mechanism. The microstructure analysis of polymer by 13 C NMR indicates atactic polymer. Another complex was also found to be efficient initiator for the ROP of trimethylene carbonate under solution and bulk conditions. Again, end-group analysis suggests coordination-insertion mechanism. V C 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 49: 5176-5185, 2011

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A series of poly(methyl methacrylate-co -methacrylic acid) (PMMA-co -MAA) random copolymers ranging in MAA content from 0-15 mol% is synthesized and blended with poly(vinylidene fl uoride) (PVDF). Using infrared spectroscopy, it is observed that the absorption bands attributed to hydrogen-bonded carbonyl groups increase in intensity as the amount of MAA in the copolymer increases. In DSC analysis, the crystallization temperature of the PVDF in the blend initially decreases by ca. 12 °C with MAA contents ranging from 0 to 5.5 mol%; however, a PVDF blend with a 15 mol% MAA copolymer has a crystallization temperature that is only ca. 3 °C below that of pure PVDF. Similarly, spherulitic growth rate analysis initially shows a decrease in radial growth rate for PVDF in blends with PMMA-co -MAA copolymers containing less than 5.5 mol% MAA. At higher MAA copolymer contents, the spherulitic growth rate approaches that of pure PVDF. It is concluded that the presence of the MAA comono mer in the PMMA-co -MAA copolymer initially (<5.5 mol% MAA) increases the intermolecular interactions between the copoly mer and the PVDF. However, as the MAA content of the copolymer rises above 5.5 mol%, intramolecular hydrogen bonding interactions within the PMMA-co -MAA copolymer cause the copoly mer to be less compatible with PVDF. been used as architectural coatings due to the excellent weathering characteristics of the partially fl uorinated PVDF blend component. [ 1 ] In these coatings applications, the degree of mixing and processing conditions of the coating can alter the crystallinity of the PVDF in the blend. [ 2 ] These variations in the crystallinity can affect the fi nal performance of the architectural coating; therefore, it is important to understand the interaction of the blend components as they pertain to the degree of mixing and crystallization. Due to the low entropy of mixing, most polymer blends will not form miscible blends unless strong intermolecular interactions exist between the blend components. These interactions can cause the blend to exhibit miscibility over a large range of composition. Studies have shown that dipole-dipole interactions between PVDF and the carbonyl group of PMMA can result in melt-compatible mixtures. [ 3 ] Relative to pure