Preparation Of Shape Stabilized Phase Change Material And Its Application In Polypropylene

Heat-storage and therm-regulated textile is manufactured by incorporating the suitable for human body temperature of phase change materials into textiles or fibers.This novel comfortable textile is able to absorb,redistribute or release heat energy by the changing of circumstance temperature at room temperature.It can be varied with the change of the environment to absorb or release heat,and maintain a constant temperature of human skin micro-climate to increase the comfort.It is an object to study the manufacture processing and properties of therm-regulated fibers in the applied and basic field.The polypropylene blend system can be prepared by traditional polypropylene melt processing.The main research content can be divided into two parts: the preparation of shape stabilized phase change materials and polypropylene/montmorillonite based shape stabilized phase change material blend system.The shape stabilized composite phase change materials were prepared by solution adsorption and intercalation method.In the composites,methoxypolyethylene glycols(MPEG1000)that was suitable behavior with the body temperature was used as phase change material.MCM-41 and MMT were used as the supporting material.The structure and phase transformation properties of the shape stabilized phase change materials were characterized and analyzed by FTIR,SEM,TGA and DSC.Polypropylene / montmorillonite based shape stabilized phase change material blend system was prepared by melt blending technoloy with polypropylene.The different contents of shape stabilized phase change materials were added into them.The structure,performance and influencing factors of the blend systems were characterized and analyzed by FTIR,SEM,TGA and DSC.The influence of the addition of shape stabilized phase change materials on the phase transformation properties of PP composite phase change materials was studied,which laid a foundation for the preparation of polypropylene fiber.The research results in this dissertation are listed as follows:(1)MPEG1000/MCM-41 shape stabilized phase change material was prepared by solution adsorption method,in which the methoxypolyethylene glycols(MPEG1000)as working medium was embedded into the support materials of MCM-41 with super high surface area.The surface morphology,structure and physical adsorption and phase change properties of MCM-41 and MPEG1000/MCM-41 shape stabilized phase change materials was chartered by SEM,BET and DSC.The results show that specific surface area of MCM-41 was up to 769.4 m/g,and MPEG1000 was immobilized on the porous structure and surfaces of MCM-41.DSC analysis was showed that with the increase of the content of MPEG1000 in MPEG1000/MCM-41 composite phase change material,the phase change enthalpy increases gradually,65% MPEG1000 was the best mass percentage in the MCM-41,the composite has larger phase change latent heat(83.3 J/g).MPEG1000 can be strongly absorbed on the active surface of MCM-41 because hydrogen boding was formed between the hydroxide groups in MPEG1000 and oxygen atom of silicon and the oxygen layer in MCM-41.and there was no obvious chemical reactions between the two components of composite materials.MPEG1000 was dispersed into the pores and surface of MCM-41.The heat storage performance test shows that MPEG1000/MCM-41 shape stabilized phase change materials have excellent performance,and there was no obvious obvious seepage was observed when the composite was kept above the melting point of MPEG1000.(2)MPEG1000/MMT shape stabilized phase change materials were prepared by solution intercalation and melting intercalation method.MPEG1000 was used as phase change material and montmorillonite clay was used as carrier material.The morphology,structure and property were characterized by SEM,FT-IR,XRD and DSC.The result shows that two kinds of shape stabilized phase change materials were prepared by different method possess had same structures.The hydrogen boding was formed between the hydroxyl groups in MPEG1000 and oxygen atom of silicon and the oxygen layer in MMT,and MPEG1000 was into the MMT layers structure by physical adsorption.The research results show that the composite materials was prepared by melting intercalation was good,47% MPEG1000 was the best mass percentage in the MMT,the composite has larger phase change latent heat(57.1J/g),the phase transition temperature of 36.6 ?C.TG analysis showed that there was no degradation of the shape stabilized phase change materials in and less than 300 ?C.The heat storage performance test shows that MPEG1000/MMT shape stabilized phase change materials have good temperature hysteresis.(3)Polypropylene was used as matrix,polypropylene/montmorillonite based shape stabilized phase change material blend system was prepared by melt blending with polypropylene resin.The dispersion of phase change materials in the blending system was analyzed by SEM.The phase transition property of the blends was analyzed by DSC,and the interaction between the components of the blends was analyzed by FTIR.The result shows that the shaped stabilized phase change material of the PP/MPEG1000/MMT blend system was in uniform and particle size is about 2~5 μm.The phase change enthalpy PP/MPEG1000/MMT blend system was up to 21.4 J/g.Compared with PP/MPEG1000 blend system,the phase change enthalpy of PP/MPEG1000/MMT blend system is 3.6 times of PP/MPEG1000 blend.The leak problem of MPEG1000 can be effectively solved by MPEG1000/MMT shape stabilized phase change materials in hot melt processing,which lays a foundation for the preparation of PP phase change fiber by melt blending technology.