
硅橡膠是指主鏈(lian)由硅(gui)和氧(yang)原子交替構成(cheng),硅(gui)原子上(shang)通常連有(you)兩(liang)個有(you)機(ji)基(ji)(ji)(ji)團的(de)(de)(de)(de)(de)橡(xiang)膠(jiao)。普(pu)通的(de)(de)(de)(de)(de)硅(gui)橡(xiang)膠(jiao)主要由含甲基(ji)(ji)(ji)和少量乙烯(xi)基(ji)(ji)(ji)的(de)(de)(de)(de)(de)硅(gui)氧(yang)鏈(lian)節組(zu)成(cheng)。苯基(ji)(ji)(ji)的(de)(de)(de)(de)(de)引入可(ke)(ke)提(ti)高(gao)硅(gui)橡(xiang)膠(jiao)的(de)(de)(de)(de)(de)耐(nai)高(gao)、低溫(wen)性(xing)(xing)能(neng),三(san)氟(fu)丙基(ji)(ji)(ji)及氰基(ji)(ji)(ji)的(de)(de)(de)(de)(de)引入則(ze)可(ke)(ke)提(ti)高(gao)硅(gui)橡(xiang)膠(jiao)的(de)(de)(de)(de)(de)耐(nai)溫(wen)及耐(nai)油性(xing)(xing)能(neng)。硅(gui)橡(xiang)膠(jiao)耐(nai)低溫(wen)性(xing)(xing)能(neng)良好,一般(ban)在(zai)(zai)(zai)-55℃下仍能(neng)工作。引入苯基(ji)(ji)(ji)后,可(ke)(ke)達(da)-73℃。硅(gui)橡(xiang)膠(jiao)的(de)(de)(de)(de)(de)耐(nai)熱性(xing)(xing)能(neng)也(ye)很突(tu)出(chu),在(zai)(zai)(zai)180℃下可(ke)(ke)長期工作,稍高(gao)于200℃也(ye)能(neng)承受數(shu)周或更長時(shi)間仍有(you)彈性(xing)(xing),瞬(shun)時(shi)可(ke)(ke)耐(nai)300℃以(yi)上(shang)的(de)(de)(de)(de)(de)高(gao)溫(wen)。硅(gui)橡(xiang)膠(jiao)的(de)(de)(de)(de)(de)透氣(qi)(qi)性(xing)(xing)好,氧(yang)氣(qi)(qi)透過率在(zai)(zai)(zai)合成(cheng)聚合物中是較高(gao)的(de)(de)(de)(de)(de)。此外,硅(gui)橡(xiang)膠(jiao)還具有(you)生(sheng)理惰性(xing)(xing)、不會導致(zhi)凝血(xue)的(de)(de)(de)(de)(de)突(tu)出(chu)特性(xing)(xing),因(yin)此在(zai)(zai)(zai)醫(yi)用領域應用廣泛。
主要品種
硅(gui)橡膠(jiao)(jiao)(jiao)分類的(de)方法(fa)很多,通(tong)常按(an)(an)固(gu)化前的(de)形態分為(wei)固(gu)體硅(gui)橡膠(jiao)(jiao)(jiao)和(he)(he)液體硅(gui)橡膠(jiao)(jiao)(jiao);按(an)(an)硫(liu)化溫(wen)(wen)(wen)度分為(wei)室溫(wen)(wen)(wen)硫(liu)化硅(gui)橡膠(jiao)(jiao)(jiao),高(gao)溫(wen)(wen)(wen)硫(liu)化硅(gui)橡膠(jiao)(jiao)(jiao);按(an)(an)所用(yong)(yong)單(dan)體的(de)不同,可分為(wei)甲基(ji)乙(yi)烯基(ji)硅(gui)橡膠(jiao)(jiao)(jiao),甲基(ji)苯基(ji)乙(yi)烯基(ji)硅(gui)橡膠(jiao)(jiao)(jiao)、氟硅(gui),腈硅(gui)橡膠(jiao)(jiao)(jiao)等;按(an)(an)性能(neng)和(he)(he)用(yong)(yong)途(tu)的(de)不同又可分為(wei)通(tong)用(yong)(yong)型、超耐(nai)低溫(wen)(wen)(wen)型、超耐(nai)高(gao)溫(wen)(wen)(wen)型、高(gao)強力型、耐(nai)油型、醫用(yong)(yong)型等等。
發展史
硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)早期是由美(mei)國(guo)(guo)以(yi)三氯化(hua)鐵為(wei)催化(hua)劑合成(cheng)的(de)(de)(de)。1945年,硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)產(chan)品問世。1948年,采用高比表面積的(de)(de)(de)氣相法白炭黑(hei)補強的(de)(de)(de)硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)研(yan)制成(cheng)功,使硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)的(de)(de)(de)性能躍(yue)升到(dao)實用階段,奠定了(le)現代硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)生產(chan)技術的(de)(de)(de)基礎(chu)。從(cong)二甲基二氯硅(gui)(gui)(gui)(gui)烷合成(cheng)開始生產(chan)硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)的(de)(de)(de)國(guo)(guo)家有美(mei)國(guo)(guo)。俄羅斯、德國(guo)(guo)、日本、韓國(guo)(guo)和中(zhong)國(guo)(guo)等(deng)。中(zhong)國(guo)(guo)硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)的(de)(de)(de)工業(ye)化(hua)研(yan)究始于1957年,多家研(yan)究所和企業(ye)陸(lu)續開發出各種(zhong)硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)。到(dao)2003年底(di),中(zhong)國(guo)(guo)硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)生產(chan)能力(li)為(wei)135千(qian)噸,其中(zhong)高溫膠(jiao)(jiao)100千(qian)噸。
高溫硫化硅橡膠
高(gao)溫硫(liu)(liu)(liu)化(hua)硅(gui)橡膠(jiao)是(shi)(shi)指聚硅(gui)氧(yang)烷變成(cheng)(cheng)彈性(xing)體的(de)過(guo)程是(shi)(shi)經(jing)過(guo)高(gao)溫(110-170℃)硫(liu)(liu)(liu)化(hua)成(cheng)(cheng)型的(de)。它主(zhu)要(yao)以高(gao)分子(zi)量的(de)聚甲基乙烯(xi)基硅(gui)氧(yang)烷為(wei)生膠(jiao),混(hun)入補(bu)強填料、硫(liu)(liu)(liu)化(hua)劑(ji)等,在加(jia)(jia)熱加(jia)(jia)壓下硫(liu)(liu)(liu)化(hua)成(cheng)(cheng)彈性(xing)體。硅(gui)橡膠(jiao)的(de)補(bu)強主(zhu)要(yao)是(shi)(shi)各(ge)(ge)種(zhong)類型的(de)白(bai)炭黑,可使硫(liu)(liu)(liu)化(hua)膠(jiao)的(de)強度增加(jia)(jia)數(shu)十倍。有時為(wei)了降低成(cheng)(cheng)本或改善膠(jiao)料性(xing)能及賦予硫(liu)(liu)(liu)化(hua)膠(jiao)各(ge)(ge)種(zhong)特(te)殊(shu)的(de)性(xing)能,也加(jia)(jia)入相應(ying)的(de)各(ge)(ge)種(zhong)添加(jia)(jia)劑(ji)。硫(liu)(liu)(liu)化(hua)劑(ji)是(shi)(shi)各(ge)(ge)種(zhong)有機過(guo)氧(yang)化(hua)物或加(jia)(jia)成(cheng)(cheng)反應(ying)催化(hua)劑(ji)。
加工成型方法如圖所示(shi)。一次(ci)硫化(hua)的目(mu)的是進(jin)(jin)行高分(fen)子鏈的交(jiao)聯(lian)反(fan)應(ying);二次(ci)硫化(hua)的目(mu)的是進(jin)(jin)行補(bu)充交(jiao)聯(lian)、驅(qu)除硫化(hua)劑分(fen)解(jie)產物和其他揮發(fa)性化(hua)合(he)物以穩定硫化(hua)膠的各(ge)項性能。常用的設備有開放式(shi)煉(lian)(lian)膠機、捏合(he)機及真空密煉(lian)(lian)機。
主要性能
(1)高(gao)(gao)溫(wen)(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)。硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)顯著的(de)(de)特征是高(gao)(gao)溫(wen)(wen)(wen)穩(wen)(wen)定(ding)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing),雖(sui)然(ran)(ran)常(chang)溫(wen)(wen)(wen)下(xia)(xia)硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)的(de)(de)強度僅是天(tian)然(ran)(ran)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)或某(mou)些合(he)成橡(xiang)(xiang)(xiang)(xiang)膠(jiao)的(de)(de)一半,但在200℃以(yi)上的(de)(de)高(gao)(gao)溫(wen)(wen)(wen)環境下(xia)(xia),硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)仍能(neng)(neng)保持一定(ding)的(de)(de)柔韌性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)、回(hui)彈性(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)能(neng)(neng)無(wu)明顯變化。(2)低溫(wen)(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)的(de)(de)玻璃(li)化溫(wen)(wen)(wen)度一般為-70~-50℃,特殊配(pei)方可(ke)達-100℃,表明其低溫(wen)(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)優(you)(you)異(yi)。這對航(hang)空(kong)、宇航(hang)工業的(de)(de)意義重大。(3)耐候性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)中Si-O-Si鍵對氧(yang)、臭氧(yang)及紫外線(xian)等十分穩(wen)(wen)定(ding),在不加任何添加劑的(de)(de)情況下(xia)(xia),就(jiu)具有優(you)(you)良的(de)(de)耐候性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)。(4)電氣性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)。硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)具有優(you)(you)異(yi)的(de)(de)絕緣性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng),耐電暈性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)和耐電弧性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)也非常(chang)好(hao)。(5)物理機械性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)。硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)常(chang)溫(wen)(wen)(wen)下(xia)(xia)的(de)(de)物理機械性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)比通用(yong)(yong)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)差(cha),但在150℃的(de)(de)高(gao)(gao)溫(wen)(wen)(wen)和-50℃的(de)(de)低溫(wen)(wen)(wen)下(xia)(xia),其物理機械性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)優(you)(you)于通用(yong)(yong)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)。(6)耐油及化學試劑性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)。普通硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)具有中等的(de)(de)耐油、耐溶(rong)劑性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)。(7)氣體(ti)(ti)(ti)透過性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)。室溫(wen)(wen)(wen)下(xia)(xia)硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)對空(kong)氣、氮、氧(yang)、二氧(yang)化碳等氣體(ti)(ti)(ti)的(de)(de)透氣性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)比天(tian)然(ran)(ran)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)高(gao)(gao)出30-50倍。(8)生(sheng)理惰性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)。硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)無(wu)毒,無(wu)味,無(wu)嗅,與人體(ti)(ti)(ti)組織不粘連,具有抗凝血作(zuo)用(yong)(yong),對肌(ji)體(ti)(ti)(ti)組織的(de)(de)反應性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)非常(chang)少。特別適(shi)合(he)作(zuo)為醫用(yong)(yong)材料(liao)。
硅橡膠的用量
據(ju)中國(guo)(guo)(guo)汽(qi)(qi)車(che)(che)工業(ye)協會統(tong)計,2012年(nian),汽(qi)(qi)車(che)(che)產(chan)銷(xiao)分(fen)別達(da)到1927.18萬輛和(he)1930.64萬輛,同比分(fen)別增(zeng)長4.63%和(he)4.33%,汽(qi)(qi)車(che)(che)工業(ye)硅(gui)橡(xiang)(xiang)膠的用(yong)(yong)量(liang)約達(da)2.0萬t。根據(ju)觀(guan)研天下(xia)的新研究,增(zeng)加有機硅(gui)材料在(zai)汽(qi)(qi)車(che)(che)零(ling)部件(jian)(jian)方面的用(yong)(yong)量(liang),可以(yi)(yi)大(da)幅度提(ti)高(gao)汽(qi)(qi)車(che)(che)的安全(quan)性能,因(yin)此(ci),汽(qi)(qi)車(che)(che)產(chan)量(liang)和(he)單(dan)車(che)(che)用(yong)(yong)量(liang)水平(ping)的提(ti)高(gao)都將推動汽(qi)(qi)車(che)(che)工業(ye)對硅(gui)橡(xiang)(xiang)膠需求的增(zeng)加。國(guo)(guo)(guo)家鼓勵自主(zhu)品牌(pai)(pai)的汽(qi)(qi)車(che)(che)發展(zhan),關(guan)鍵(jian)汽(qi)(qi)車(che)(che)零(ling)部件(jian)(jian)實現自主(zhu)化(hua),《2012年(nian)度黨(dang)政(zheng)機關(guan)公務用(yong)(yong)車(che)(che)選用(yong)(yong)車(che)(che)型目錄(lu)(征求意見(jian)稿)》為(wei)自主(zhu)品牌(pai)(pai)擴大(da)在(zai)政(zheng)府采購(gou)的市(shi)場份額,為(wei)改變目前國(guo)(guo)(guo)內政(zheng)府采購(gou)以(yi)(yi)合資品牌(pai)(pai)產(chan)品為(wei)主(zhu)的局面提(ti)供(gong)了保障。促進自主(zhu)品牌(pai)(pai)發展(zhan),國(guo)(guo)(guo)產(chan)汽(qi)(qi)車(che)(che)業(ye)的繁(fan)榮將為(wei)汽(qi)(qi)車(che)(che)膠的應(ying)用(yong)(yong)提(ti)供(gong)有力(li)保障。預(yu)測未(wei)來(lai)3年(nian),我(wo)國(guo)(guo)(guo)室溫硫化(hua)硅(gui)橡(xiang)(xiang)膠在(zai)汽(qi)(qi)車(che)(che)行業(ye)將以(yi)(yi)年(nian)均20%增(zeng)長。
此外(wai),硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)是重要的(de)(de)(de)非(fei)石(shi)(shi)油(you)(you)基(ji)合(he)成(cheng)(cheng)(cheng)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao),約占非(fei)石(shi)(shi)油(you)(you)基(ji)合(he)成(cheng)(cheng)(cheng)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)消費量的(de)(de)(de)98%。但(dan)因(yin)為石(shi)(shi)油(you)(you)價格的(de)(de)(de)大幅上漲(zhang),同時我國在硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)的(de)(de)(de)關鍵原料有(you)(you)(you)機硅(gui)(gui)單體(ti)的(de)(de)(de)生產技(ji)術方(fang)(fang)面取得突破,有(you)(you)(you)機硅(gui)(gui)單體(ti)的(de)(de)(de)生產技(ji)術在2005年前被(bei)幾(ji)家跨國公司壟斷,但(dan)目前我國已發展(zhan)成(cheng)(cheng)(cheng)為全(quan)球有(you)(you)(you)機硅(gui)(gui)單體(ti)第(di)1大國,這2個方(fang)(fang)面原因(yin)使硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)的(de)(de)(de)價格從2011年起開始低于石(shi)(shi)油(you)(you)基(ji)合(he)成(cheng)(cheng)(cheng)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao),僅約為大宗石(shi)(shi)油(you)(you)基(ji)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)的(de)(de)(de)80%~90%,成(cheng)(cheng)(cheng)為廉價的(de)(de)(de)合(he)成(cheng)(cheng)(cheng)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao),并(bing)開始大規(gui)模(mo)替代石(shi)(shi)油(you)(you)基(ji)合(he)成(cheng)(cheng)(cheng)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)。這將(jiang)極大拓展(zhan)有(you)(you)(you)機硅(gui)(gui)產業的(de)(de)(de)市場空間(jian),同時將(jiang)帶動硅(gui)(gui)油(you)(you)、硅(gui)(gui)烷偶聯(lian)劑和(he)硅(gui)(gui)樹脂等其他有(you)(you)(you)機硅(gui)(gui)產品(pin)的(de)(de)(de)消費。