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Peroxidation, epoxidation, and/or perepoxidation reactions of soybean oil under air at room temperature resulted in cross-linked polymeric soybean oil peroxides on the surface along with the waxy soluble part, sPSB, with a molecular weight of 4690, containing up to 2.3 wt % peroxide. This soluble polymeric oil peroxide, sPSB, initiated the free radical polymerization of either methyl methacrylate (MMA) or n-butyl methacrylate (nBMA) to give PSB-g-PMMA and PSB-g-PnBMA graft copolymers. The polymers obtained were characterized by ¹H NMR, thermogravimetric analysis, differential scanning calorimetry, and gel permeation chromatography techniques. Polymeric oil as a plasticizer lowered the glass transition of the PSB-g-PMMA graft copolymers. PSB-g-PMMA and PSB-g-PnBMA graft copolymer film samples were also used in cell culture studies. Fibroblast and macrophage cells were strongly adhered and spread on the copolymer film surfaces, which is important in tissue engineering. Bacterial adhesion on PSB-g-PMMA graft copolymer was also studied. Both Staphylococcus epidermidis and Escherichia coli adhered on the graft copolymer better than on homo-PMMA. Furthermore, the latter adhered much better than the former.

Chlorination of microbial polyesters poly(3-hydroxybutyrate) (PHB) and poly(3-hydroxyoctanoate) (PHO) was carried out by passing chlorine gas through their solutions. The chlorine contents in chlorinated PHB (PHB-Cl) and chlorinated PHO (PHO-Cl) were between 5.45 and 23.81 wt % and 28.09 and 39.09 wt %, respectively. Molecular weights of the chlorinated samples were in the range of between one-half to one-fourth of the original values because of hydrolysis during the chlorination process. Thermal properties of the PHO-Cl were dramatically changed with an increase in its glass transition (Tg = 2 °C) and the melting transition (Tm). The Tg of PHB-Cl varied from −20 to 10 °C, and its Tm decreased to 148 °C. The chlorinated poly(3-hydroxyalkanoate)s (PHA-Cl) were converted to their corresponding quaternary ammonium salts (PHA-N⁺R3), sodium sulfate salts (PHA-S), and phenyl derivatives (PHA-Ph). Cross-linked polymers were also formed by a Friedel−Crafts reaction between benzene and PHA-Cl. The modified PHO derivatives were characterized by ¹H NMR and ¹³C NMR spectrometry, Fourier transform infrared spectroscopy, gel permeation chromatography, and differential scanning calorimetry techniques.

Synthesis of an α,β-alkyl branched polyester, i.e., poly(2-methyl-3-hydroxyoctanoate), has been accomplished via anionic polymerization of α-methyl-β-pentyl-β-propiolactone mediated by supramolecular complexes of potassium methoxide or potassium hydroxide, respectively. The structure of resulting polymers has been established by electrospray ionization multistage mass spectrometry (ESI−MSⁿ), FT-IR, NMR, and GPC analyses. Previously proposed addition−elimination mechanism of the polymerization of β-lactones containing α-hydrogen by alkoxide anion has been confirmed to operate also in the case of β-lactone having alkyl substituents in both α and β positions.

Unsaturated biopolyesters, (PHA−DB), obtained from pure anchovy (hamci), hazelnut, soybean oily acids and the mixtures of octanoic acid (in weight ratios of 50/50 and 70/30) were chlorinated up to 54 wt % Cl content. The molecular weights (MW) of the chlorinated biopolyesters were between 1.3 × 10⁴ and 3.0 × 10⁴ and decreased with the increase in chlorine content in PHA−DB. Melting transitions of the chlorinated biopolyesters were between 62 and 125 °C depending on the chlorine content when compared with those of the original PHAs, 44−55 °C.

The dispersion copolymerization of methyl methacrylate (MMA) with macromonomeric azoinitiator, MIM-400, as a macrocrosslinker initiated by the benzoyl peroxide (BPO)/N,N′dimethylaniline (DMA) coupled in water/ethanol (4/1, v/v) at 20°C was carried out to yield PEG-b-PMMA networks with labile azo linkages in the main chain. Gel fraction, swelling ratios (qv) and the average molecular weights between junction points (Mc) values of the networks were investigated. Maximum gel fraction was obtained using 0.133M MIM-400, 9.2×10−2M BPO, 2.1×10−2M DMA and 2.19M MMA.

Two transscaphoid perilunate dislocations of the wrist, treated by trapeziolunate external fixation-1 after closed and the other after open reduction-are reported.

Pseudomonas oleovorans was grown separately on 5-(4‘-tolyl)valeric acid, 5-(4‘-ethylphenyl)valeric acid, 5-(4‘-biphenyl)valeric acid, and 8-(4‘-tolyl)octanoic acid either as the sole carbon source or as a coefeed with either nonanoic acid or 5-phenylvaleric acid. For polymer production, 5-(4‘-tolyl)valeric acid was the most effective growth substrate of the five. It resulted in the production of poly-3-hydroxy-5-(4‘-tolyl)valerate, a crystalline polymer with a glass transition temperature of 18 °C and a melting transition of 95 °C. This poly(3-hydroxyalkanoate) (PHA) is apparently the first example of a crystalline aromatic-containing bacterial PHA. When P. oleovorans was cofed an equimolar mixture of 5-phenylvaleric acid and 5-(4‘-tolyl)valeric acid, the polymer produced contained 36 mol % of 3-hydroxy-5-phenylvalerate and 64 mol % of 3-hydroxy-5-(4‘-tolyl)valerate, and it did not crystallize.

A new type of macroinimers were synthesized by the capping reaction of hydroxyl groups of polyazoesters with isocyanato ethyl, methacrylate in the presence of dibutyl tin dilaurate. Macroinimers having PEG-400 and PEG-1500 units were used in the polymerization of methyl methacrylate (MMA) or styrene (S) to obtain PS-PEG or PMMA-PEG branched block copolymers at 60°C. Longer polymerization times or higher macroinimer concentrations led to cross-linked block copolymers. Similarly neat homopolymerization of macroinimers also led to the cross-linked polyethyleneglycols. The products were characterized by IR and NMR spectroscopy, viscosity measurements and fractional precipitation.