Effect of dosage of expandable graphite,dimethyl methylphosphonate,triethanolamine,and isocyanate on fluidity,mechanical,and flame retardant properties of polyurethane materials in coal reinforcement  

作　　者：Hu Xiangming Wang Deming Cheng Weimin 

机构地区：[1]Key Laboratory of Gas and Fire Control for Coal Mines of Ministry of Education,Faculty of Safety Engineering,China University of Mining and Technology [2]Key Laboratory of Mine Disaster Prevention and Control,College of Resource and Environmental Engineering,Shandong University of Science and Technology [3]Department of Resources and Environment,Binzhou University

出　　处：《International Journal of Mining Science and Technology》2016年第2期345-352,共8页矿业科学技术学报（英文版）

基　　金：supported by the National Natural Science Foundation of China(No.51304027);China Postdoctoral Science Foundation(2014M560567 and 2015T80730);Shandong Province Science and Technology Development Plan(2014GSF120012);the State Key Program of Coal Joint Funds of National Natural Science Foundation of China(Nos.51134020 and U1261205);Shandong Province Natural Science Foundation(No.ZR2011EL036);the Doctoral Scientific Research Foundation of Binzhou University(No.2013Y06);the Key Technology Projects for Preventing Major Accident of National Security State Administration of Work Safety

摘　　要：In this study,orthogonal experiments were conducted to investigate the influence of expandable graphite(EG),dimethyl methylphosphonate(DMMP),triethanolamine(TEA),and isocyanate content on the compressive and bonding strengths,oxygen index,and fluidity of rigid polyurethane foam(RPUF).The results revealed that EG significantly increased the oxygen index of RPUF,enlarged the diameter of foam cells,and decreased the cell-closed content in foam;thus,leading to a pressure drop in RPUF.However,excessive EG was capable of reducing the fluidity of polyurethane slurry.TEA exhibited significant influence on the compressive strength of RPUF,which dropped initially,and then increased.DMMP had a remarkable effect on the flame retardant property and compressive strength of RPUF.Compressive strength of RPUF initially displayed an increase followed by a decrease with increasing dosage of DMMP,and achieved the maximum value at DMMP dosage of 4%.DMMP could effectively reduce the diameter of RPUF cells leading to an increase in the percentage of close area in foam.DMMP displayed the flame-retardation effects mainly in the gas phase leading to a significant enhancement in the oxygen index of RPUF.Moreover,the compressive strength and bonding strength of RPUF decrease significantly with the increase of isocyanate content due to the increased blowing efficiency by the CO_2.The oxygen index and flowing length of foam increased with the increase in isocyanate dosage.In this study,orthogonal experiments were conducted to investigate the influence of expandable graphite（EG）,dimethyl methylphosphonate（DMMP）,triethanolamine（TEA）,and isocyanate content on the compressive and bonding strengths,oxygen index,and fluidity of rigid polyurethane foam（RPUF）.The results revealed that EG significantly increased the oxygen index of RPUF,enlarged the diameter of foam cells,and decreased the cell-closed content in foam;thus,leading to a pressure drop in RPUF.However,excessive EG was capable of reducing the fluidity of polyurethane slurry.TEA exhibited significant influence on the compressive strength of RPUF,which dropped initially,and then increased.DMMP had a remarkable effect on the flame retardant property and compressive strength of RPUF.Compressive strength of RPUF initially displayed an increase followed by a decrease with increasing dosage of DMMP,and achieved the maximum value at DMMP dosage of 4%.DMMP could effectively reduce the diameter of RPUF cells leading to an increase in the percentage of close area in foam.DMMP displayed the flame-retardation effects mainly in the gas phase leading to a significant enhancement in the oxygen index of RPUF.Moreover,the compressive strength and bonding strength of RPUF decrease significantly with the increase of isocyanate content due to the increased blowing efficiency by the CO_2.The oxygen index and flowing length of foam increased with the increase in isocyanate dosage.

关 键 词：Rigid polyurethane foam Expandable graphite Compressive strength Flame retardant Scanning electron microscopy（SEM） Microstructure 

分 类 号：TQ328.3[化学工程—合成树脂塑料工业]