Thermo Acrylonitrile - Methyl Methacrylate Copolymer Film

The phase change material can absorb and release energy by the change of phase when the definite environmental temperature changes. Microencapsulated n-octadecane (MOCT) can prevent phase change material from leaking and can be used in thermo-regulated fibers, also endow the fiber with good thermal property. Various mole ratios of acrylonitrile (AN) and methyl methacrylate (MMA) were used to copolymerize in aqueous solution by Redox and the copolymers were obtained. The copolymers containing MOCT were synthesized by adding MOCT before copolymerization. The copolymer were derived from the copolymerization of AN and MMA in 30L kettle and then were mixed with various contents of MOCT, the copolymer films were cast by solution of the copolymer containing MOCT. The fabrication of fibers was attempted. The copolymers, the copolymers containing MOCT and the copolymer films containing MOCT were characterized by using Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), Differential Scanning Calorimetry (DSC), Thermogravimetric Analyzer (TG) and X-ray Diffraction (XRD) etc. The conclusions were summarized as following,1. The AN/MMA copolymers were testified that copolymerization of most AN and MMA occurred and the ratio of AN and MMA in copolymer was less than the ratio of monomers. With the increase of the contents of MMA, the viscosity of copolymer solution, molecular weight and decomposition temperature of copolymers increase. The thermal stability of 85/15AN/MMA is best among all of the copolymers.2. The MOCT are distributed in the copolymers and inserted into the copolymer matrix. The heat-absorbing temperatures (T_m) and the heat-evolving temperatures (T_c) of the MOCT in copolymers are almost the same as that of MOCT respectively. With the content of MOCT increasing the viscosity and the efficiency of enthalpy of MOCT increase and the heat-resistant temperatures of the MOCT in copolymers rise and approach that of the MOCT, the crystallinity also increases but the thermal stability of the copolymer in the sample decreases.3. The copolymer derived from the copolymerization in high capacity kettle were testified that copolymerization between AN and MMA occurred. The microcapsules in the films are distributed in the copolymer film matrix. The heat-absorbing temperatures and heat-evolving temperatures of the films are almost the same as that of the MOCT, respectively. In addition, the enthalpy efficiency of MOCT, the melting enthalpy and the crystallizing enthalpy rises with the contents of MOCT increasing.The decomposition temperature of copolymers in the films containing various contents of MOCT decreases with the contents of MOCT increasing. The crystallinity of the film increases with the contents of MOCT increasing.4. The content of MMA cannot influence the melting temperatures of copolymers. The addition of MOCT can make the melting temperatures of copolymer decrease and the valuable conclusion can be derived. The MOCT in copolymer has the highest melting enthalpy, crystallizing enthalpy, melting enthalpy efficiency, crystallizing enthalpy efficiency comparing to the MOCT in copolymer films and fibers.