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To diversify edible oil thermoresponsive polymer composites, polymeric linoleic acid peroxide (PLina) and polymeric linolenic acid peroxide (PLinl) were obtained by the autoxidation of linoleic acid (Lina) and linolenic acid (Linl), respectively. The autoxidation of Lina and Linl under air at room temperature rendered waxy soluble polymeric peroxide, having a soluble fraction in chloroform of more than 91 wt% and containing up to 1.0 wt% of peroxide. The soluble polymeric oil macroperoxide was used to initiate the free radical polymerization of N-isopropylacrylamide, NIPAM, resulting in PLina-g-PNIPAM and PLinl-g-PNIPAM graft copolymers, respectively. The PNIPAM content of the graft copolymers was calculated using the elemental nitrogen analysis of graft copolymers. Thermal analysis, FTIR, 1 H NMR, and SEM techniques were used in the characterization of the products. The hydrophobic effect of the fatty acid macro peroxides on the thermal response rate of the graft copolymers was investigated by means of swellingdeswelling behaviors in response to temperature change. They have a thermoresponsive character and exhibit a volume phase transition at approximately 27-30°C, which is 1-4°C lower than that of pure PNIPAM. A plastizer effect of PLina and PLinl in graft copolymers was observed, indicating a lower glass transition temperature than that of pure PNIPAM.

One‐pot synthesis of graft copolymers by ring‐opening polymerization and free radical polymerization using polymeric linoleic acid peroxide (PLina) is reported. Graft copolymers having structures of poly(linoleic acid)‐g‐polystyrene‐g‐poly(ε‐caprolactone) were synthesized from PLina, possessing peroxide groups on the main chain by the combination of free radical polymerization of styrene and ring‐opening polymerization of ε‐caprolactone in one‐step. Principal parameters, such as monomer concentration, initiator concentration, and polymerization time, which effect the one‐pot polymerization reactions were evaluated. The obtained graft copolymers were characterized by 1H‐NMR and DOSY‐NMR spectroscopy, gel permeation chromatography, thermal gravimetric analysis and differential scanning calorimetry techniques.

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Macromonomer initiators behave as macro cross-linkers, macro initiators, and macromonomers to obtain branched and cross-linked block/graft copolymers. A series of new macromonomer initiators for atom transfer radical polymerization (MIM-ATRP) based on polyethylene glycol (M n ¼ 495D, 2203D, and 4203D) (PEG) were synthesized by the reaction of the hydroxyl end of mono-methacryloyl polyethylene glycol with 2-bromo propanoyl chloride, leading to methacryloyl polyethylene glycol 2-bromo propanoyl ester. Poly (ethylene glycol) functionalized with methacrylate at one end was reacted with 2-bromopropionyl chloride to form a macromonomeric initiator for ATRP. ATRP was found to be a more controllable polymerization method than conventional free radical polymerization in view of fewer cross-linked polymers and highly branched polymers produced from macromonomer initiators as well. In another scenario, ATRP of N-isopropylacrylamide (NIPAM) was initiated by MIM-ATRP to obtain PEG-b-PNIPAM branched block/graft copolymers. Thermal analysis, FTIR, 1 H NMR, TEM, and SEM techniques were used in the characterization of the products. They had a thermo-responsive character and exhibited volume phase transition at $ 36 C. A plasticizer effect of PEG in graft copolymers was also observed, indicating a lower glass transition temperature than that of pure PNIPAM. Homo and copolymerization kinetics were also evaluated.