XIAOYAN LIU^a,*, XU CHEN^a, HONGXING ZHANG^b, CHANGJUN ZHANG^a, SHIYUAN YANG^a, GUANGQUAN LI^a

Journal of Polymer Materials, Vol.36, No.2, pp. 121-132, 2019, DOI:10.32381/JPM.2019.36.02.2

Abstract In this work, three in situ impact polypropylene copolymer(IPC) samples were prepared through Ziegler-Natta catalyst only changing the feed composition (ethylene to ethylene and propylene molar ratio, C2/C2+C3) in gas-phase polymerization reactor. Polymer (IPC) were characterical by solvent classification, gel permeation chromatography (GPC), differential scanning calorimetry (DSC), successive self-nucleation and annealing (SSA), nuclear magnetic resonance(13C-NMR) and scanning electron microscopy(SEM). The mechanical properties of IPC samples were tested.The results indicate that with similar ethylene content, the feed composition which determines the content and structure of EPR and EbP component in IPC, further impacts the rubber phase size and distribution in IPC,… More >

Yodthong Baimark^*, Theeraphol Phromsopha

Journal of Renewable Materials, Vol.11, No.4, pp. 1881-1894, 2023, DOI:10.32604/jrm.2023.025400

Abstract A poly(L-lactide)-b-poly(ethylene glycol)-b-poly(L-lactide)(PLLA-PEG-PLLA) block copolymer has great potential for use as a flexible bioplastic. Highly flexible bioplastics are required for flexible packaging applications. In this work, a PEG was incorporated into block copolymer as a plasticizer by solvent casting. PLLA-PEG-PLLA/ PEG blends with different blend ratios were prepared, and the plasticizing effect and miscibility of PEG in block copolymer were intensively investigated compared to PLLA/PEG blends. The results indicated that the PEG was an effective plasticizer for the block copolymer. The blending of PEG decreased glass-transition temperature and accelerated the crystallization of both the PLLA and PLLA-PEG-PLLA matrices. The PEG… More > Graphic Abstract