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Postconsumer PET bottles including water and soft-drink bottles were depolymerized by glycolysis in excess glycols, such as ethylene glycol, propylene glycol, and diethylene glycol, in the presence of a zinc acetate catalyst. The obtained glycolyzed products were reacted with maleic anhydride and mixed with a styrene monomer to prepare unsaturated polyester (UPE) resins. These resins were cured using methyl ethyl ketone peroxide (MEKPO) as an initiator and cobalt octoate as an accelerator. The physical and mechanical properties of the cured samples were investigated. It was found that the type of glycol used in glycolysis had a significant effect on the characteristics of the uncured and cured UPE resins. Uncured EG-based UPE resin was a soft solid at room temperature, whereas uncured PG-and DEG-based resins were viscous liquids. In the case of the cured resins, the EG-based product exhibited characteristics of a hard and brittle plastic, while the PG-based product did not. The DEG-based product exhibited characteristics of hard and brittle plastic after strain-induced crystallization had occurred. In addition, it was also found that no separation of the type of bottles was needed before glycolysis, since UPE resins prepared from water bottles, soft-drink bottles, and a mixture of both bottles showed the same characteristics.

Water-reducible acrylic-alkyd resins were synthesized from the reaction between monoglycerides prepared from modified palm oil and carboxy-functional acrylic copolymer followed by neutralization of carboxyl groups with diethanolamine. Modified palm oil was produced by interesterification of palm oil with tung oil at a weight ratio of 1 : 1, using sodium hydroxide as a catalyst, whereas carboxy-functional acrylic copolymer was prepared by radical copolymerization of n-butyl methacrylate and maleic anhydride. The amount of acrylic copolymer used was from 15 to 40% by weight, and it was found that homogeneous resins was obtained when the copolymer content was 20 -35 wt %. All of the prepared water-reducible acrylic-alkyd resins were yellowish viscous liquids. Their films were dried by baking at 190°C and their properties were determined. These films showed excellent water and acid resistance and good alkali resistance.

This study aimed to improve the brittleness and thermal stability of poly(lactic acid) (PLA) by inclusion of poly(butylene succinate) (PBS) and microcrystalline cellulose (MCC). Of the three PLA/PBS blends (10, 30 and 50 wt% PBS) evaluated, the 70/30 wt% blend exhibited the highest impact strength and elongation at break, but a lower thermal stability compared to that of the pure PLA. Scanning electron microscopy analysis confirmed the better compatibility of this 70/30 PLA/PBS blend. This blend was further filled with MCC. Based on thermogravimetric analysis, the thermal stability of the 70/30 PLA/PBS blend was improved by the addition of MCC [optimal at five parts by weight per hundred (phr)] and further still by the addition of the chain extender, Joncryl TM , at 0.5 phr. The 70/30/5/0.5 PLA/PBS/MCC/Joncryl TM composite exhibited the highest impact strength, while the elongation at break was acceptable.