导热阻燃聚氨酯复合材料的制备

发布时间：2018-01-11 15:40

本文关键词：导热阻燃聚氨酯复合材料的制备　出处：《华南理工大学》2015年硕士论文　论文类型：学位论文

【摘要】：电子产品领域中,产品向高集成度、高功率、高频率的方向发展,对材料性能的要求越来越高,不仅要求良好的导热性能,还要求良好的力学、阻燃、电绝缘、加工性能等。因而高分子材料越来越受关注。聚氨酯(PU)弹性体具有优异的综合性能,如强度较高、硬度范围较宽、耐磨性优异、耐疲劳性良好等,且性能可调程度大,特别适用于制备兼具多种优异性能的高分子材料。本文通过分子设计合成了强度、硬度和耐热性兼优的PU,并通过填充不同的填料获得良好的阻燃和导热性能。这种材料制造成本较低、功能多样,具有良好的市场发展前景。本文使用聚四氢呋喃二醇(PTMG)、聚醚多元醇4110(4110)、六亚甲基二异氰酸酯三聚体(HDI三聚体)和三乙醇胺(TEOA)合成了PU弹性体,研究了PTMG、4110和TEOA的用量对PU拉伸性能和硬度的影响,并讨论了TEOA和4110的加入对PU热性能的影响。当TEOA和4110的用量分别为醇类单体总量(TA-OH)的25 wt%和38wt%时,PU的强度、硬度和热性能兼优,拉伸强度为27.2 MPa,冲击不断,邵D硬度为70°,5 wt%失重的温度为306℃,且PU交联密度较高,热导率为0.272 W/(m·K),极限氧指数(LOI值)为25.1%,不能通过UL94 V-0级。采用磷酸和聚氧化丙烯三醇为原料,本文合成了聚氧化丙烯三醇磷酸酯(PPT-P),并用来改性氢氧化铝(ATH)和氧化镁(MgO),分别制备了ATH-P和MgO-P。PPT-P具有PU软段结构,能明显改善ATH和MgO与PU的相容性。填充量相同时,PU/ATH-P比PU/ATH具有更高的力学和阻燃性能,PU/MgO-P比PU/MgO具有更高的力学、导热和阻燃性能以及热性能。采用ATH-P为阻燃填料,填充量为40 vol%时,PU/ATH-P兼具良好的力学和阻燃性能,拉伸强度为23.8 MPa,能通过UL94 V-0级,但其导热性能不佳。以MgO-P为导热填料,填充量为45 vol%时,PU/MgO-P兼具良好的力学和导热性能,拉伸强度为27.9MPa,热导率为1.276 W/(m-K),但阻燃性能无法达到UL94 V-0级。为了制备兼具良好导热和阻燃性能的复合材料,以ATH-P部分取代MgO-P。当MgO-P和ATH-P的填充量分别为30 vol%和15 vo1%时,PU/MgO-P/ATH-P的导热和阻燃性能较好,热导率为1.009 W/(m·K),可以通过UL94 V-0级。在此用量下,ATH-P和MgO-P具有协效导热和阻燃作用。改变MgO的粒径和形状,可进一步提高PU/MgO-P/ATH-P的导热性能,如采用形状不规则和粒径分布较宽的a-MgO-P代替片状的MgO-P对,复合材料在通过UL94 V-0级的同时,其热导率提高了34%,为1.356 W/(m·K)。
[Abstract]:In the field of electronic products, the development of products towards high integration, high power, high frequency, the requirements for material properties are becoming higher and higher, not only requires good thermal conductivity, but also requires good mechanical, flame retardant, electrical insulation. Pu) elastomer has excellent comprehensive properties, such as high strength, wide range of hardness, excellent wear resistance, good fatigue resistance and so on. Especially suitable for the preparation of polymer materials with many excellent properties. In this paper, pu with excellent strength, hardness and heat resistance was synthesized by molecular design. Good flame retardancy and thermal conductivity were obtained by filling different fillers. This kind of material has low cost, various functions and good market prospect. In this paper, PTMG is used. Pu elastomer was synthesized from polyether polyol (4110), hexamethylene diisocyanate trimer (hexamethylene diisocyanate trimer) and triethanolamine (PTMG). The effects of 4110 and TEOA contents on the tensile properties and hardness of pu. The influence of the addition of TEOA and 4110 on the thermal properties of pu was discussed. When the amount of TEOA and 4110 was 25 wt% and 38 wt% of the total alcohol monomer, respectively. The strength, hardness and thermal property of pu are excellent, the tensile strength is 27.2 MPa, the impact is constant, the temperature of weight loss of Shao D is 70 掳~ 5 wt%, and the crosslinking density of pu is high. The thermal conductivity is 0.272W / m 路KN, the limit oxygen index (loi) is 25.1and cannot pass through UL94 V-0. Phosphoric acid and polypropylene triol are used as raw materials. In this paper, polypropylene triol phosphate (PPT-PX) was synthesized and used to modify aluminum hydroxide (ATH) and magnesium oxide (MgO). ATH-P and MgO-P.PPT-P have soft segment structure of pu, which can obviously improve the compatibility of ATH and MgO with pu. PU/ATH-P has higher mechanical and flame retardant properties than PU/ATH. PUP / MgO-P has higher mechanical properties than PU/MgO. Thermal conductivity, flame retardancy and thermal properties. ATH-P was used as the flame-retardant filler with good mechanical and flame-retardant properties when the content of the filler was 40 vol%. The tensile strength is 23.8 MPA and can pass through UL94 V-0 grade, but its thermal conductivity is not good. When MgO-P is used as thermal conductive filler, the filling amount is 45 vol%. PU/MgO-P has good mechanical and thermal conductivity, tensile strength is 27.9MPa, thermal conductivity is 1.276W / m ~ (-1). But the flame-retardant property can not reach UL94 V-0 grade. In order to prepare composite material with good thermal conductivity and flame retardant property. MgO-P. was partially replaced by ATH-P. When the contents of MgO-P and ATH-P were 30 volt% and 15 vo1%, respectively. The thermal conductivity and flame retardancy of PU/MgO-P/ATH-P are better, and the thermal conductivity is 1.009 W / m 路KG, which can be passed through UL94 V-0 grade. ATH-P and MgO-P have synergistic heat conduction and flame retardant effect. Changing the diameter and shape of MgO can further improve the thermal conductivity of PU/MgO-P/ATH-P. If the a-MgO-P with irregular shape and wide particle size distribution is used to replace the flake MgO-P pair, the thermal conductivity of the composites increases by 34% while passing through the UL94 V-0 grade. It is 1.356 W / L 路KN.
【学位授予单位】：华南理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TQ334;TB33

【引证文献】