更新时间:10-18 上传会员:在职研究生
分类:环境科学 论文字数:8099 需要金币:1000个
摘要:聚硅氮烷是一种无机聚合物,其主链由硅、氮原子交替排列组成,可作为Si-C-N陶瓷的先驱体,用于制造Si-C-N陶瓷纤维、薄膜等材料。
早在上世纪二十年代就开始对其进行研究,但是研究进展缓慢。直到20世纪60年代,研究者们将目光投向设计合适的聚硅氮烷分子结构。自此,聚硅氮烷作为陶瓷前驱体聚合物成为研究热点。
聚硅氮烷作为一种新兴的合成材料,继承了氮化硅基复合材料的高强度、高硬度、低密度、低热膨胀系数等优点。聚硅氮烷自问世以来一直以良好的耐高温性能著称,所以它在陶瓷基体方面得到了广泛的研究。除此之外,随着对聚硅氮烷的研究逐步深入,发现其还具备抗氧化、耐腐蚀、防辐射、透波等卓越的性能,适应于高强辐射的特殊环境中。因而聚硅氮烷也被制成涂层、薄膜材料广泛的运用到航空航天、军事等领域,是一种应用于特殊环境中的新兴聚合物材料。
本文是通过控制乙烯基含量,以甲基氢二氯硅烷、甲基乙烯基二氯硅、二甲基二氯硅烷为原料,按一定配比进行氨解反应,合成一种新型的聚硅氮烷(PSN-Vi),并对合成产物的性质进行检测与表征,进一步了解新型聚硅氮烷的性能。
关键词: 聚硅氮烷,乙烯基,合成,表征
Abstract:The polysilazane is an inorganic polymer, the main chain composed of silicon, nitrogen atoms are alternately arranged, can be used as the Si-CN ceramic Precursor, ceramic fibers, films, and other materials used in the manufacture of a Si-CN.
As early as in the twenties began to study it, but slow progress. Until the 1960s, researchers will turn their attention to design suitable the polysilazane molecular structure. Since then, the polysilazane as ceramic precursor polymer become a hot topic.
Polysilazane as a new synthetic materials, inherited the advantages of the silicon nitride matrix composites, high-strength, high hardness, low density, low thermal expansion coefficient. The the polysilazane since its inception has been known for good high temperature performance, it has been widely studied in the ceramic matrix. In addition to time, in-depth with the polysilazane research gradually found that it also has anti-oxidation, corrosion, radiation, wave-transparent superior performance, adapt to the radiation in the high-strength special environment. The polysilazane therefore also be made of coated film material widely used in aerospace, military and other fields, the emerging polymer material is a used in special environments.
This is the control vinyl content, methylhydrogen dichlorosilane, vinyl methyl dichloro silicon, dimethyl dichlorosilane as raw material, the ammonolysis reaction according to a certain proportion, the synthesis of a novel polysilazane alkyl (PSN-Vi), and the nature of the synthetic product detection and characterization Learn more about the performance of the new polysilazane.
Key Words:Polysilazane Vinyl Synthesis Characterization
聚硅氮烷是一种无机聚合物,其主链是以重复≡Si-N=单元组成的。纵观聚硅氮烷的发展历程,其可大致分为四阶段:首先是上世纪二十年代开始,研究者开始尝试合成硅氮烷环体和齐聚物,并对其进行分类,但这段时期聚硅氮烷发展缓慢。20世纪60年代研究者们提出了合成环二、环三、环四硅氮烷的方法,并研究其主要性质,期望能够以聚合物的形式应用,但研究进展基本停止不前。之后研究者们将目光投向设计合适的聚硅氮烷分子结构,以此来制备Si3N4和Si-C-N纤维。这段时间,研究者将研究的重心主在聚硅氮烷可纺性以及如何固化裂解上。自此,聚硅氮烷作为陶瓷前驱体聚合物成为研究热点。上世纪70年代末,我国以谢择民为代表的化学家研究聚硅氮烷并将其应用于硅橡胶中。九十年代,通过向聚硅氮烷中引入B元素制备得到Si-B-C-N陶瓷,带动着研究者们将目光投向改性聚硅氮烷,以制具有更高耐温性的Si-C-N陶瓷。之后,磁性Si-Fe-C-N陶瓷、抗菌性Si-Ag-C-N陶瓷、抗结晶性Si-Zr-C-N陶瓷等相继制备出来。
自问世以来一直以良好的耐高温性能著称,因此其在陶瓷前驱体方面得到了广泛的研究,并将其应用在陶瓷基复合材料、陶瓷纤维、多孔陶瓷等材料的制备方面。聚硅氮烷还具有良好的加工性能、热稳定性、透波性能,目前其应用已扩展到陶瓷薄膜、树脂微电子机械系统(MEMS)等领域。同时聚硅氮烷还具有非常好的抗氧化、耐腐蚀、防辐射,被制成涂层材料大量运用到航空航天、军事等特殊环境中。