A series of stearates with different rare-earth ion were investigated as thermal stabilizers for rigid PVC at 180 ℃ in air. Their stabilizing efficiency was based on measuring the rate of dehydrochlorination. The res...A series of stearates with different rare-earth ion were investigated as thermal stabilizers for rigid PVC at 180 ℃ in air. Their stabilizing efficiency was based on measuring the rate of dehydrochlorination. The resulted revealed the higher stabilizing efficiency of the investigated rare-earth stearates as thermal stabilizers for rigid PVC compared with the thermal stabilizers for industry: calcium stearate, zinc stearate, butyl stannum mercaptide, phosphite esters, β-diketone and epoxidized sunflower oil. This was well illustrated by longer incubation period (T_S) values and lower rate of dehydrochlorination. The stable efficiency was affected by the nature of rare-earth element's individual electronic shell. The mechanism for the stabilizing effect of rare-earth stearates was proposed. The result was experimentally proved based on IR spectrum.展开更多
Glycerol stearate was synthesized by esterification with non-toxic,inexpensive glycerol and stearic acid.The composite of glycerol stearate and Pinus radiata wood was prepared by vacuum impregnation.By Fourier transfo...Glycerol stearate was synthesized by esterification with non-toxic,inexpensive glycerol and stearic acid.The composite of glycerol stearate and Pinus radiata wood was prepared by vacuum impregnation.By Fourier transform infrared(FTIR)analysis,there was the generation of new C=O stretching vibration band of glycerol stearate in comparison with stearic acid.This confirms that glycerol stearate was successfully synthesized.The weight gain,FTIR spectrum and morphological analyses of the composite indicate that glycerol stearate was impregnated into the interior lumina of the cells.Thermal analysis showed that the maximal degradation temperature of the composite was 42℃higher than untreated wood.Contact angle images indicated that the value of the composite was134.2°.Hydrophobicity(the repulsion of water)of the composite was stronger than glycerol stearate,which a large number of hydroxyl of wood reacted with the oxygen-containing groups of glycerol stearate,improved hydrophobicity and thermal stability,thereby enhancing the potential application of P.radiata wood.展开更多
Influences of lanthanum stearate （LaSt3） and calcium stearate/zinc stearate （Ca/Zn） stabilizers on stabilization efficiency of dibutyltin dilaurate （DBTDL） to polyvinyl chloride （PVC） in air were investigated....Influences of lanthanum stearate （LaSt3） and calcium stearate/zinc stearate （Ca/Zn） stabilizers on stabilization efficiency of dibutyltin dilaurate （DBTDL） to polyvinyl chloride （PVC） in air were investigated. The results revealed that the stabilization effect of DBTDL could be achieved by the La/Sn stabilizers with a ratio of 8/2. Addition of DBTDL could enhance thermal property and reduce dynamic storage modulus （G＇） at 180℃ for PVC containing LaSt3 or Ca/Zn stabilizers. On the other hand, incorporation of LaSh did not influence the stabilization efficiency of DBTDL markedly; while addition of Ca/Zn stabilizers could significantly decrease thermal property for the DBTDL stabilized PVC. Furthermore, the effects of LaSt3 and Ca/Zn stabilizers on the stabilization efficiency of DBTDL were explained in the framework of ionization potential.展开更多
文摘A series of stearates with different rare-earth ion were investigated as thermal stabilizers for rigid PVC at 180 ℃ in air. Their stabilizing efficiency was based on measuring the rate of dehydrochlorination. The resulted revealed the higher stabilizing efficiency of the investigated rare-earth stearates as thermal stabilizers for rigid PVC compared with the thermal stabilizers for industry: calcium stearate, zinc stearate, butyl stannum mercaptide, phosphite esters, β-diketone and epoxidized sunflower oil. This was well illustrated by longer incubation period (T_S) values and lower rate of dehydrochlorination. The stable efficiency was affected by the nature of rare-earth element's individual electronic shell. The mechanism for the stabilizing effect of rare-earth stearates was proposed. The result was experimentally proved based on IR spectrum.
基金funded by the Fundamental Research Funds for the Central Universities(No.2572017CB24)the Postdoctoral Scientific Research Starting Foundation of Heilongjiang Province(No.LBH-Q17004)
文摘Glycerol stearate was synthesized by esterification with non-toxic,inexpensive glycerol and stearic acid.The composite of glycerol stearate and Pinus radiata wood was prepared by vacuum impregnation.By Fourier transform infrared(FTIR)analysis,there was the generation of new C=O stretching vibration band of glycerol stearate in comparison with stearic acid.This confirms that glycerol stearate was successfully synthesized.The weight gain,FTIR spectrum and morphological analyses of the composite indicate that glycerol stearate was impregnated into the interior lumina of the cells.Thermal analysis showed that the maximal degradation temperature of the composite was 42℃higher than untreated wood.Contact angle images indicated that the value of the composite was134.2°.Hydrophobicity(the repulsion of water)of the composite was stronger than glycerol stearate,which a large number of hydroxyl of wood reacted with the oxygen-containing groups of glycerol stearate,improved hydrophobicity and thermal stability,thereby enhancing the potential application of P.radiata wood.
基金supported by Key Projects in the National Science & Technology Pillar Program(No. 2007BAE10B04)
文摘Influences of lanthanum stearate （LaSt3） and calcium stearate/zinc stearate （Ca/Zn） stabilizers on stabilization efficiency of dibutyltin dilaurate （DBTDL） to polyvinyl chloride （PVC） in air were investigated. The results revealed that the stabilization effect of DBTDL could be achieved by the La/Sn stabilizers with a ratio of 8/2. Addition of DBTDL could enhance thermal property and reduce dynamic storage modulus （G＇） at 180℃ for PVC containing LaSt3 or Ca/Zn stabilizers. On the other hand, incorporation of LaSh did not influence the stabilization efficiency of DBTDL markedly; while addition of Ca/Zn stabilizers could significantly decrease thermal property for the DBTDL stabilized PVC. Furthermore, the effects of LaSt3 and Ca/Zn stabilizers on the stabilization efficiency of DBTDL were explained in the framework of ionization potential.
