需要金幣:1000 個金幣 | 資料包括:完整論文,開題報告,任務(wù)書 | ||
轉(zhuǎn)換比率:金額 X 10=金幣數(shù)量, 例100元=1000金幣 | 論文字?jǐn)?shù):8099 | ||
折扣與優(yōu)惠:團(tuán)購最低可5折優(yōu)惠 - 了解詳情 | 論文格式:Word格式(*.doc) |
摘要:聚硅氮烷是一種無機(jī)聚合物,其主鏈由硅、氮原子交替排列組成,可作為Si-C-N陶瓷的先驅(qū)體,用于制造Si-C-N陶瓷纖維、薄膜等材料。 早在上世紀(jì)二十年代就開始對其進(jìn)行研究,但是研究進(jìn)展緩慢。直到20世紀(jì)60年代,研究者們將目光投向設(shè)計合適的聚硅氮烷分子結(jié)構(gòu)。自此,聚硅氮烷作為陶瓷前驅(qū)體聚合物成為研究熱點。 聚硅氮烷作為一種新興的合成材料,繼承了氮化硅基復(fù)合材料的高強度、高硬度、低密度、低熱膨脹系數(shù)等優(yōu)點。聚硅氮烷自問世以來一直以良好的耐高溫性能著稱,所以它在陶瓷基體方面得到了廣泛的研究。除此之外,隨著對聚硅氮烷的研究逐步深入,發(fā)現(xiàn)其還具備抗氧化、耐腐蝕、防輻射、透波等卓越的性能,適應(yīng)于高強輻射的特殊環(huán)境中。因而聚硅氮烷也被制成涂層、薄膜材料廣泛的運用到航空航天、軍事等領(lǐng)域,是一種應(yīng)用于特殊環(huán)境中的新興聚合物材料。 本文是通過控制乙烯基含量,以甲基氫二氯硅烷、甲基乙烯基二氯硅、二甲基二氯硅烷為原料,按一定配比進(jìn)行氨解反應(yīng),合成一種新型的聚硅氮烷(PSN-Vi),并對合成產(chǎn)物的性質(zhì)進(jìn)行檢測與表征,進(jìn)一步了解新型聚硅氮烷的性能。 關(guān)鍵詞: 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
聚硅氮烷是一種無機(jī)聚合物,其主鏈?zhǔn)且灾貜?fù)≡Si-N=單元組成的。縱觀聚硅氮烷的發(fā)展歷程,其可大致分為四階段:首先是上世紀(jì)二十年代開始,研究者開始嘗試合成硅氮烷環(huán)體和齊聚物,并對其進(jìn)行分類,但這段時期聚硅氮烷發(fā)展緩慢。20世紀(jì)60年代研究者們提出了合成環(huán)二、環(huán)三、環(huán)四硅氮烷的方法,并研究其主要性質(zhì),期望能夠以聚合物的形式應(yīng)用,但研究進(jìn)展基本停止不前。之后研究者們將目光投向設(shè)計合適的聚硅氮烷分子結(jié)構(gòu),以此來制備Si3N4和Si-C-N纖維。這段時間,研究者將研究的重心主在聚硅氮烷可紡性以及如何固化裂解上。自此,聚硅氮烷作為陶瓷前驅(qū)體聚合物成為研究熱點。上世紀(jì)70年代末,我國以謝擇民為代表的化學(xué)家研究聚硅氮烷并將其應(yīng)用于硅橡膠中。九十年代,通過向聚硅氮烷中引入B元素制備得到Si-B-C-N陶瓷,帶動著研究者們將目光投向改性聚硅氮烷,以制具有更高耐溫性的Si-C-N陶瓷。之后,磁性Si-Fe-C-N陶瓷、抗菌性Si-Ag-C-N陶瓷、抗結(jié)晶性Si-Zr-C-N陶瓷等相繼制備出來。 自問世以來一直以良好的耐高溫性能著稱,因此其在陶瓷前驅(qū)體方面得到了廣泛的研究,并將其應(yīng)用在陶瓷基復(fù)合材料、陶瓷纖維、多孔陶瓷等材料的制備方面。聚硅氮烷還具有良好的加工性能、熱穩(wěn)定性、透波性能,目前其應(yīng)用已擴(kuò)展到陶瓷薄膜、樹脂微電子機(jī)械系統(tǒng)(MEMS)等領(lǐng)域。同時聚硅氮烷還具有非常好的抗氧化、耐腐蝕、防輻射,被制成涂層材料大量運用到航空航天、軍事等特殊環(huán)境中。
|