
硅橡膠是(shi)指主鏈(lian)由硅(gui)和(he)氧原子(zi)交替構成,硅(gui)原子(zi)上通常連有兩個有機基(ji)(ji)團(tuan)的橡膠(jiao)(jiao)。普(pu)通的硅(gui)橡膠(jiao)(jiao)主要由含(han)甲基(ji)(ji)和(he)少量乙烯基(ji)(ji)的硅(gui)氧鏈(lian)節組成。苯(ben)基(ji)(ji)的引入可(ke)提高(gao)(gao)硅(gui)橡膠(jiao)(jiao)的耐(nai)(nai)(nai)高(gao)(gao)、低(di)溫(wen)(wen)性能(neng),三氟丙基(ji)(ji)及氰基(ji)(ji)的引入則可(ke)提高(gao)(gao)硅(gui)橡膠(jiao)(jiao)的耐(nai)(nai)(nai)溫(wen)(wen)及耐(nai)(nai)(nai)油性能(neng)。硅(gui)橡膠(jiao)(jiao)耐(nai)(nai)(nai)低(di)溫(wen)(wen)性能(neng)良(liang)好,一般在(zai)-55℃下仍(reng)(reng)能(neng)工作。引入苯(ben)基(ji)(ji)后,可(ke)達-73℃。硅(gui)橡膠(jiao)(jiao)的耐(nai)(nai)(nai)熱性能(neng)也很突出(chu),在(zai)180℃下可(ke)長(chang)(chang)期工作,稍高(gao)(gao)于(yu)200℃也能(neng)承受數周或(huo)更長(chang)(chang)時間仍(reng)(reng)有彈性,瞬時可(ke)耐(nai)(nai)(nai)300℃以上的高(gao)(gao)溫(wen)(wen)。硅(gui)橡膠(jiao)(jiao)的透(tou)氣性好,氧氣透(tou)過率在(zai)合成聚(ju)合物中是(shi)較高(gao)(gao)的。此外,硅(gui)橡膠(jiao)(jiao)還(huan)具有生理(li)惰性、不會導(dao)致凝血的突出(chu)特性,因此在(zai)醫用(yong)領域(yu)應(ying)用(yong)廣泛。
主要品種
硅(gui)(gui)橡膠(jiao)分類的(de)方法很多,通(tong)(tong)常按(an)(an)固化(hua)前的(de)形態分為(wei)(wei)固體硅(gui)(gui)橡膠(jiao)和(he)液體硅(gui)(gui)橡膠(jiao);按(an)(an)硫(liu)化(hua)溫(wen)度(du)分為(wei)(wei)室溫(wen)硫(liu)化(hua)硅(gui)(gui)橡膠(jiao),高(gao)(gao)溫(wen)硫(liu)化(hua)硅(gui)(gui)橡膠(jiao);按(an)(an)所(suo)用(yong)單體的(de)不同,可分為(wei)(wei)甲(jia)基(ji)乙烯(xi)(xi)基(ji)硅(gui)(gui)橡膠(jiao),甲(jia)基(ji)苯基(ji)乙烯(xi)(xi)基(ji)硅(gui)(gui)橡膠(jiao)、氟硅(gui)(gui),腈硅(gui)(gui)橡膠(jiao)等(deng);按(an)(an)性能和(he)用(yong)途的(de)不同又可分為(wei)(wei)通(tong)(tong)用(yong)型(xing)(xing)、超耐(nai)低溫(wen)型(xing)(xing)、超耐(nai)高(gao)(gao)溫(wen)型(xing)(xing)、高(gao)(gao)強(qiang)力(li)型(xing)(xing)、耐(nai)油型(xing)(xing)、醫用(yong)型(xing)(xing)等(deng)等(deng)。
發展史
硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)早期是由美國(guo)(guo)(guo)以三(san)氯(lv)(lv)化鐵(tie)為(wei)催化劑合(he)成(cheng)的(de)。1945年,硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)產(chan)品問世。1948年,采用(yong)高比表面積的(de)氣相法(fa)白炭黑補(bu)強(qiang)的(de)硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)研制(zhi)成(cheng)功,使(shi)硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)的(de)性能躍升(sheng)到實用(yong)階段,奠定(ding)了現代硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)生產(chan)技術的(de)基礎。從二甲基二氯(lv)(lv)硅(gui)(gui)(gui)烷合(he)成(cheng)開始生產(chan)硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)的(de)國(guo)(guo)(guo)家有美國(guo)(guo)(guo)。俄羅(luo)斯(si)、德國(guo)(guo)(guo)、日本、韓國(guo)(guo)(guo)和中(zhong)國(guo)(guo)(guo)等。中(zhong)國(guo)(guo)(guo)硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)的(de)工業(ye)化研究始于1957年,多(duo)家研究所和企業(ye)陸(lu)續開發出各(ge)種硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)。到2003年底(di),中(zhong)國(guo)(guo)(guo)硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)生產(chan)能力(li)為(wei)135千噸(dun),其(qi)中(zhong)高溫膠(jiao)(jiao)100千噸(dun)。
高溫硫化硅橡膠
高溫硫(liu)(liu)化(hua)(hua)硅(gui)橡膠是(shi)指(zhi)聚硅(gui)氧(yang)烷變成(cheng)彈性(xing)體(ti)的(de)(de)過程是(shi)經過高溫(110-170℃)硫(liu)(liu)化(hua)(hua)成(cheng)型(xing)的(de)(de)。它(ta)主要以(yi)高分(fen)子量的(de)(de)聚甲基乙(yi)烯基硅(gui)氧(yang)烷為(wei)生(sheng)膠,混(hun)入補(bu)強(qiang)填(tian)料、硫(liu)(liu)化(hua)(hua)劑等,在加(jia)熱(re)加(jia)壓下硫(liu)(liu)化(hua)(hua)成(cheng)彈性(xing)體(ti)。硅(gui)橡膠的(de)(de)補(bu)強(qiang)主要是(shi)各(ge)種(zhong)類型(xing)的(de)(de)白炭(tan)黑(hei),可使硫(liu)(liu)化(hua)(hua)膠的(de)(de)強(qiang)度增加(jia)數十(shi)倍。有(you)時為(wei)了降(jiang)低成(cheng)本或(huo)改善膠料性(xing)能及賦予硫(liu)(liu)化(hua)(hua)膠各(ge)種(zhong)特殊的(de)(de)性(xing)能,也加(jia)入相應(ying)的(de)(de)各(ge)種(zhong)添加(jia)劑。硫(liu)(liu)化(hua)(hua)劑是(shi)各(ge)種(zhong)有(you)機(ji)過氧(yang)化(hua)(hua)物或(huo)加(jia)成(cheng)反應(ying)催化(hua)(hua)劑。
加工成型方(fang)法如圖所示。一(yi)次硫(liu)化(hua)(hua)的(de)目(mu)的(de)是進(jin)行(xing)高分子鏈的(de)交聯反應;二次硫(liu)化(hua)(hua)的(de)目(mu)的(de)是進(jin)行(xing)補(bu)充交聯、驅除硫(liu)化(hua)(hua)劑分解產物和其他揮發性化(hua)(hua)合物以穩定(ding)硫(liu)化(hua)(hua)膠(jiao)的(de)各(ge)項(xiang)性能。常用的(de)設備(bei)有(you)開放式(shi)煉(lian)膠(jiao)機(ji)、捏合機(ji)及真空密煉(lian)機(ji)。
主要性能
(1)高(gao)(gao)(gao)溫(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)。硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)顯著的(de)特(te)征是(shi)高(gao)(gao)(gao)溫(wen)(wen)穩(wen)定(ding)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing),雖然常溫(wen)(wen)下(xia)(xia)硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)的(de)強度僅是(shi)天(tian)然橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)或某些合成橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)的(de)一(yi)半(ban),但(dan)在200℃以(yi)上的(de)高(gao)(gao)(gao)溫(wen)(wen)環境下(xia)(xia),硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)仍能(neng)(neng)(neng)保持一(yi)定(ding)的(de)柔韌性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)、回(hui)彈(dan)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)和表面硬度,且力學性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)無(wu)明顯變化(hua)。(2)低溫(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)的(de)玻璃化(hua)溫(wen)(wen)度一(yi)般為-70~-50℃,特(te)殊配(pei)方可達-100℃,表明其低溫(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)優(you)異。這對航空(kong)、宇航工業(ye)的(de)意(yi)義重大。(3)耐候性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)中Si-O-Si鍵對氧(yang)、臭氧(yang)及紫外(wai)線等十分穩(wen)定(ding),在不加(jia)任何添加(jia)劑的(de)情況下(xia)(xia),就具有優(you)良的(de)耐候性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)。(4)電(dian)氣(qi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)。硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)具有優(you)異的(de)絕緣性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng),耐電(dian)暈性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)和耐電(dian)弧性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)也非常好(hao)。(5)物(wu)理(li)機(ji)械性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)。硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)常溫(wen)(wen)下(xia)(xia)的(de)物(wu)理(li)機(ji)械性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)比(bi)通用橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)差,但(dan)在150℃的(de)高(gao)(gao)(gao)溫(wen)(wen)和-50℃的(de)低溫(wen)(wen)下(xia)(xia),其物(wu)理(li)機(ji)械性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)優(you)于通用橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)。(6)耐油及化(hua)學試(shi)劑性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)。普(pu)通硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)具有中等的(de)耐油、耐溶劑性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)。(7)氣(qi)體透過性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)。室(shi)溫(wen)(wen)下(xia)(xia)硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)對空(kong)氣(qi)、氮(dan)、氧(yang)、二氧(yang)化(hua)碳等氣(qi)體的(de)透氣(qi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)比(bi)天(tian)然橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)高(gao)(gao)(gao)出30-50倍。(8)生理(li)惰性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)。硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)無(wu)毒,無(wu)味,無(wu)嗅,與人體組織(zhi)(zhi)不粘連,具有抗(kang)凝血作用,對肌體組織(zhi)(zhi)的(de)反應性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)非常少。特(te)別適(shi)合作為醫用材料。
硅橡膠的用量
據(ju)中國汽(qi)(qi)車(che)(che)(che)工業(ye)協會統計,2012年(nian),汽(qi)(qi)車(che)(che)(che)產(chan)(chan)(chan)銷分別達到1927.18萬輛和1930.64萬輛,同比分別增(zeng)長(chang)(chang)4.63%和4.33%,汽(qi)(qi)車(che)(che)(che)工業(ye)硅橡膠(jiao)的(de)用量約(yue)達2.0萬t。根據(ju)觀研天下的(de)新研究(jiu),增(zeng)加有機(ji)硅材料在(zai)(zai)汽(qi)(qi)車(che)(che)(che)零(ling)部(bu)件方面(mian)(mian)的(de)用量,可(ke)以(yi)大幅度(du)提高汽(qi)(qi)車(che)(che)(che)的(de)安全性能,因(yin)此,汽(qi)(qi)車(che)(che)(che)產(chan)(chan)(chan)量和單(dan)車(che)(che)(che)用量水平的(de)提高都將(jiang)推動汽(qi)(qi)車(che)(che)(che)工業(ye)對硅橡膠(jiao)需(xu)求(qiu)的(de)增(zeng)加。國家鼓勵自(zi)(zi)主(zhu)品(pin)(pin)牌的(de)汽(qi)(qi)車(che)(che)(che)發展,關(guan)鍵汽(qi)(qi)車(che)(che)(che)零(ling)部(bu)件實現自(zi)(zi)主(zhu)化,《2012年(nian)度(du)黨政(zheng)(zheng)機(ji)關(guan)公(gong)務用車(che)(che)(che)選用車(che)(che)(che)型(xing)目錄(征求(qiu)意見稿)》為自(zi)(zi)主(zhu)品(pin)(pin)牌擴大在(zai)(zai)政(zheng)(zheng)府采購的(de)市場份額,為改(gai)變目前國內政(zheng)(zheng)府采購以(yi)合(he)資品(pin)(pin)牌產(chan)(chan)(chan)品(pin)(pin)為主(zhu)的(de)局面(mian)(mian)提供(gong)了保(bao)障。促進自(zi)(zi)主(zhu)品(pin)(pin)牌發展,國產(chan)(chan)(chan)汽(qi)(qi)車(che)(che)(che)業(ye)的(de)繁榮將(jiang)為汽(qi)(qi)車(che)(che)(che)膠(jiao)的(de)應用提供(gong)有力保(bao)障。預測未來(lai)3年(nian),我國室溫硫化硅橡膠(jiao)在(zai)(zai)汽(qi)(qi)車(che)(che)(che)行業(ye)將(jiang)以(yi)年(nian)均20%增(zeng)長(chang)(chang)。
此(ci)外,硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)是(shi)重要的(de)(de)非石(shi)油(you)(you)基(ji)(ji)(ji)合成橡(xiang)(xiang)(xiang)(xiang)膠(jiao),約占(zhan)非石(shi)油(you)(you)基(ji)(ji)(ji)合成橡(xiang)(xiang)(xiang)(xiang)膠(jiao)消費量的(de)(de)98%。但因(yin)為石(shi)油(you)(you)價格的(de)(de)大幅上(shang)漲(zhang),同時(shi)我(wo)國在硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)的(de)(de)關(guan)鍵原料有(you)機(ji)(ji)硅(gui)(gui)(gui)(gui)單(dan)(dan)(dan)體(ti)的(de)(de)生(sheng)(sheng)產技術(shu)方面取得(de)突破,有(you)機(ji)(ji)硅(gui)(gui)(gui)(gui)單(dan)(dan)(dan)體(ti)的(de)(de)生(sheng)(sheng)產技術(shu)在2005年(nian)前(qian)被(bei)幾家跨國公(gong)司壟斷,但目前(qian)我(wo)國已(yi)發展成為全球有(you)機(ji)(ji)硅(gui)(gui)(gui)(gui)單(dan)(dan)(dan)體(ti)第(di)1大國,這2個方面原因(yin)使硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)的(de)(de)價格從2011年(nian)起開始低(di)于石(shi)油(you)(you)基(ji)(ji)(ji)合成橡(xiang)(xiang)(xiang)(xiang)膠(jiao),僅約為大宗(zong)石(shi)油(you)(you)基(ji)(ji)(ji)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)的(de)(de)80%~90%,成為廉價的(de)(de)合成橡(xiang)(xiang)(xiang)(xiang)膠(jiao),并開始大規模替代(dai)石(shi)油(you)(you)基(ji)(ji)(ji)合成橡(xiang)(xiang)(xiang)(xiang)膠(jiao)。這將極大拓展有(you)機(ji)(ji)硅(gui)(gui)(gui)(gui)產業(ye)的(de)(de)市場空間(jian),同時(shi)將帶(dai)動硅(gui)(gui)(gui)(gui)油(you)(you)、硅(gui)(gui)(gui)(gui)烷偶聯劑和硅(gui)(gui)(gui)(gui)樹脂等其他有(you)機(ji)(ji)硅(gui)(gui)(gui)(gui)產品的(de)(de)消費。