Preparation Of Polyethylene Glycol N - Alkyl Vinyl Ether And Application Of Fiber

Energy is the basis for human survival and development. The demand for energy is greatly increasing with the economic development as well as the social progress. Therefore, it has become a popular issue to search for new energy sources and improve energy efficiency. Comb-like polymeric phase change materials taken an intermediate place between the branched and the linear polymer are extensively used as modified materials to get better physical and chemical properties.In present work, (di)ethyleneglycol hexadecyl (octadecyl) vinyl ether (CmEnVE(m=1,2;n=16,18)) as a phase change material was fabricated using (di)ethylene glycol monovinyl ether sodium and bromohexadecane (bromooctadecane) as raw materials through sodium alkoxide method. Poly(ethylene glycol hexadecyl vinyl ether)(PC16E1VE) and Poly(ethylene glycol octadecyl vinyl ether)(PC18E1VE) were synthesized by living cationic polymerization. Sheath-core polymeric nanofibers were coaxially electro-spun using it as the core material, and poly(acrylonitrile-co-vinylidene chloride). The molecular weight and its distribution were characterized using gel permeation chromatography. The surface morphology and the sheath-core structure were observed using scanning electronic microscope and transmission electronic microscope, respectively. The structure, phase change properties, thermal stability of CmEnVE(m=1,2;n=16,18), PC16E1VE and the nanofibers were characterized using Fourier transform infrared spectroscopy, hydrogen nuclear magnetic resonance spectrum, differential scanning calorimetry, and thermogravimetric analysis.The results show that, CmEnVE(m=1,2;n=16,18), PC16E1VE, PC18EiVE and the nanofiber are excellent phase change materials with steady structure, high heat enthalpy and thermal stability. Both the melting and crystallizing enthalpies of PC16E1VE are about 84 J/g. The peak melting temperature and crystallizing temperature are 27.5 and 17.5 ℃, respectively. Also, both the melting and crystallizing enthalpies of PC18E1VE are about 87 J/g. The peak melting temperature and crystallizing temperature are 29.1 and 17.3℃, respectively.It is thermal stable below 200 ℃. These properties indicate that this phase change material can be widely used as a polymeric phase change material in high temperature environments. When the concentration of the P(AN-co-VDC) aqueous solution and PC16E1VE spinning solutions were 15 wt%,60 wt% and spun at flow rates of 1.25 mL/h,0.375 mL/h, respectively. The fibers show uniform diameters and stable core-sheath structures.Both the melting and crystallizing enthalpies of nanofibers are about 46 J/g. The peak melting temperature and crystallizing temperature are 34.7 and 23.5 ℃, respectively. It is a heat energy storage material with excellent properties.