聚异氰脲酸酯-硅气凝胶复合绝热材料的制备及性能研究

发布时间：2018-05-27 17:14

本文选题：PIR硬泡 + 硅气凝胶　；参考：《西南科技大学》2015年硕士论文

【摘要】：本文针对隔热保温材料存在的热稳定性低、阻燃性能差等问题,提出了将聚氨酯泡沫材料与硅气凝胶进行复合的设计思路,利用聚氨酯泡沫材料的热导率低、抗压强度高、产烟量低与硅气凝胶的质轻、低导热系数、优隔热性能、高孔隙率相结合,制备出一种热稳定性能优越、阻燃性能好的复合绝热硬质泡沫材料。本文采用一步法成功制备了新型的聚异氰脲酸酯硬泡(PIR)/硅气凝胶复合材料,研究了掺入颗粒状Si O2气凝胶对复合材料阻燃性、热稳定性及力学性能的影响,主要结论如下:(1)初步探究了颗粒状硅气凝胶的三种不同形态对复合材料的影响,发现:湿气凝胶会降低复合材料的性能,干颗粒状的硅气凝胶形态所制备出的PIR复合材料泡沫的性能最佳。另外,基体b体系PIR基体泡沫制备的复合材料要比基体a体系PIR基体泡沫制备的复合材料的性能优,尤其是热稳定性和阻燃性。(2)为了降低体系的粘度和提高硅气凝胶的用量,所以我们应该选择基体b体系低粘度的聚乙二醇600为原料制备PIR复合材料泡沫,从而使复合材料泡沫在基体中具有良好的分散性能。不仅颗粒状硅气凝胶用量达到了8%(wt.%),而且这个低粘度体系下的基体泡沫的氧指数为29.4,也达到了报道中最高聚氨酯的阻燃值。PIR复合材料泡沫相比基体泡沫的氧指数提高到了34.6%;复合材料泡沫的抗压强度提高了136%,比强度增加了92.2%。TG曲线上显示复合材料的热稳定性随着硅气凝胶含量的增加而显著提高,残余质量增加了20.4%;热导率相比基体泡沫降低了32.7%(从硅气凝胶剂量的0%-8%),加入颗粒状Si O2气凝胶的复合材料保温效果提高。(3)FT-IR表明硅气凝胶的加入没有改变聚氨酯的化学结构,在聚氨酯基体中仅作了无机填料的成分。从SEM看出,加入适量Si O2气凝胶的复合材料可以得到较好的泡孔结构且泡孔排列规整,并有了显著的改善,与基体泡沫相比,复合材料的泡孔结构较小,泡孔密度较大,其力学性能较好。(4)为了进一步降低复合材料泡沫的成本,我们引入硅气凝胶基础上添加了一种废渣多元醇。结果表明:单掺废渣多元醇的复合材料,除了力学性能有稍微的降低,其他相关性能都有所提高。然而基体b中同时加入废渣多元醇和颗粒状的硅气凝胶制备的PIR复合材料泡沫能够提高阻燃性和保温性能,其抗压强度提高25.4%,比强度提高22.0%。热稳定性提高了61.8%,氧指数增加了17.0%,热导率降低了27.5%,泡孔的孔隙率有所下降。总而言之,废渣多元醇和颗粒状硅气凝胶的同时添加提高了材料性能,还降低了成本。
[Abstract]:Aiming at the problems of low thermal stability and poor flame retardancy of thermal insulation materials, this paper puts forward the design idea of composite polyurethane foam materials with silicon aerogels. The low thermal conductivity and high compressive strength of polyurethane foam materials are used in this paper. A composite heat insulating rigid foam with excellent thermal stability and good flame retardancy was prepared by combining low smoke production with light weight, low thermal conductivity, excellent thermal insulation and high porosity of silicon aerogel. In this paper, a new type of polyisocyanurate rigid foam PIRN / silicon aerogel composite was successfully prepared by one step method. The effects of particle Sio 2 aerogel on the flame retardancy, thermal stability and mechanical properties of the composite were studied. The main conclusions are as follows: (1) the effects of three different forms of granular silica aerogels on composite materials are investigated. The properties of PIR composite foam prepared by dry granular silicon aerogel were the best. In addition, the composites prepared by matrix b PIR matrix foam are superior to those prepared by matrix a PIR matrix foam, especially the thermal stability and flame-retardance of the composites, in order to reduce the viscosity of the system and increase the amount of silicon aerogel. So we should choose polyethylene glycol 600 with low viscosity in matrix b system as raw material to prepare PIR composite foam, so that composite foam has good dispersion property in matrix. Not only did the amount of granular silica aerogel reach 8%, but also the oxygen index of matrix foam in this low viscosity system was 29.4, which also reached the highest flame retardant value of polyurethane, the oxygen index of PIR composite foam compared with matrix foam in this low viscosity system. The compressive strength of the composite foam increased by 136.The specific strength of the composite foam increased by 136.The 92.2%.TG curve showed that the thermal stability of the composite increased significantly with the increase of the content of silica aerogel. The residual mass was increased by 20.4 and the thermal conductivity was reduced by 32.7than that of the matrix foam. (from the dose of silica aerogel to 0-8%), the thermal insulation effect of composite added granular Sio _ 2 aerogel was improved. FT-IR showed that the addition of silicon aerogel did not change the chemical structure of polyurethane. Only inorganic filler was used in polyurethane matrix. SEM shows that the composite with proper amount of Sio _ 2 aerogel can obtain a better bubble structure and a regular arrangement of the bubble pores, and has a significant improvement. Compared with the matrix foam, the composite has a smaller bubble structure and a larger density of the bubble pores, and the structure of the composite is better than that of the matrix foam, and the pore density of the composite is larger than that of the matrix foam. In order to further reduce the cost of composite foam, a kind of waste residue polyol was added on the basis of silicon aerogel. The results show that the mechanical properties of the composites with only waste residue polyols have been slightly reduced, and the other related properties have been improved. However, the PIR composite foam prepared by adding waste residue polyol and granular silicon aerogel into the matrix b can improve the flame retardancy and thermal insulation property, its compressive strength is increased by 25.4and the specific strength is increased by 22.0. The thermal stability increased by 61.8, the oxygen index increased by 17.0, the thermal conductivity decreased by 27.5 and the porosity of the bubble decreased. In a word, waste residue polyol and granular silica aerogel can improve the properties of the material and reduce the cost.
【学位授予单位】：西南科技大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TB332

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