Preparation And Properties Of Alkylated Poly (Ethylene - G - Maleic Anhydride) Comb Polymer

Phase change materials (PCMs), as one of green thermal energy storage materials, have been widely utilized in the aspect of energy saving buildings, solar energy storage and recycling of waste heat energy. However, typical PCMs appear the volume expansion, liquid leakage problems and bad thermal stability during the solid-liquid phase change process. Comb-like polymeric PCMs exhibit good advantages because of the protection of the polymer backbone. Therefore, the study of synthesis, property and confinement behaviour under the nanoscale space of comb-like polymeric PCMs has attracted lots of attentions.In this study, a series of shape-stabilized comb-like polymeric phase change materials, denoted as EMA-g-CnH2n+1OH with n=14,16,18,26, are prepared. The structure and thermal property of EMA-g-CnH2n+1OH are characterized by FTIR、1H NMR、XRD、DSC and TG. The characterizations show that EMA-g-CnH2n+1OH have good shape stability, high enthalpy, good crystallization and thermal stability. Moreover, EMA-g-CnH2n+1OH show good heat energy storage and release ability. The time of heat storage and release during the solid-liquid transition process was 205 and 49 second, respectively. EMA-g-CnH2n+1OH demonstrates the good thermal reliability and structure stability properties after 300 thermal cycles.Coaxial nanofiber of PET/EMA-g-C18H37OH NF has been successfully fabricated through electrospinning technology (EST), which poly(ethylene-graft-maleic anhydride)-g-octadecyl alcohol (EMA-g-C18H37OH) acts as core component and poly(ethylene terephthalate) (PET) as shell component. After that, composite filtration membrane (CFM) is prepared through non-solvent phase separation method, using PVDF as base membrane solution and coaxial nanofiber membrane as supporting layer. SEM and DSC demonstrate that the CFM has good porosity and heat energy storage. CFM shows the high water flux and rejection of BSA, and the water flux is as high as 1400 L/(m2·h). When the water flux of CFM is less than 300 L/(m2·h), the rejection of BSA is more than 85%. The CFM also exhibits temperature sentative property during the phase change temperature range of it.Coaxial nanofiber (PET/PSMA NF) with good orientation has been fabricated via EST. Composite membrane (CM) is fabricated using PS as membrane solution and PET/PSMA NF as supporting layer. The microstructure and crystalling behavior of PET/PSMA NF and CM are characterized by SEM and XRD. The confinement behavior of PSMA containing hard-confinement, soft-confinement as well as the middle-confinement in the PET/PSMA NF and CM after different temperature heating treatment is studied by DSC and non-isothermal crystallization kinetics method.