
硅橡膠是指(zhi)主鏈由硅(gui)和氧原子交(jiao)替構成(cheng),硅(gui)原子上通常連(lian)有兩個有機基(ji)團的(de)橡(xiang)(xiang)膠(jiao)。普通的(de)硅(gui)橡(xiang)(xiang)膠(jiao)主要由含甲基(ji)和少量乙烯基(ji)的(de)硅(gui)氧鏈節組(zu)成(cheng)。苯(ben)基(ji)的(de)引入可(ke)(ke)提(ti)高(gao)硅(gui)橡(xiang)(xiang)膠(jiao)的(de)耐(nai)高(gao)、低溫性能(neng),三氟丙基(ji)及(ji)氰基(ji)的(de)引入則(ze)可(ke)(ke)提(ti)高(gao)硅(gui)橡(xiang)(xiang)膠(jiao)的(de)耐(nai)溫及(ji)耐(nai)油(you)性能(neng)。硅(gui)橡(xiang)(xiang)膠(jiao)耐(nai)低溫性能(neng)良好(hao),一般(ban)在(zai)(zai)(zai)-55℃下仍能(neng)工(gong)作。引入苯(ben)基(ji)后,可(ke)(ke)達-73℃。硅(gui)橡(xiang)(xiang)膠(jiao)的(de)耐(nai)熱(re)性能(neng)也(ye)很突(tu)出(chu),在(zai)(zai)(zai)180℃下可(ke)(ke)長(chang)期工(gong)作,稍高(gao)于200℃也(ye)能(neng)承受數周或更長(chang)時間仍有彈性,瞬時可(ke)(ke)耐(nai)300℃以上的(de)高(gao)溫。硅(gui)橡(xiang)(xiang)膠(jiao)的(de)透氣性好(hao),氧氣透過率在(zai)(zai)(zai)合成(cheng)聚合物(wu)中是較高(gao)的(de)。此外,硅(gui)橡(xiang)(xiang)膠(jiao)還具有生理惰性、不會(hui)導致凝(ning)血的(de)突(tu)出(chu)特性,因(yin)此在(zai)(zai)(zai)醫用領域應用廣泛(fan)。
主要品種
硅橡膠分類(lei)的方法(fa)很多(duo),通(tong)常按固化(hua)
前的形態分(fen)(fen)(fen)為(wei)(wei)固體硅(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)和液體硅(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao);按硫(liu)化溫(wen)度分(fen)(fen)(fen)為(wei)(wei)室溫(wen)硫(liu)化硅(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao),高(gao)(gao)溫(wen)硫(liu)化硅(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao);按所用(yong)單(dan)體的不(bu)同(tong),可(ke)分(fen)(fen)(fen)為(wei)(wei)甲基乙烯基硅(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao),甲基苯(ben)基乙烯基硅(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)、氟硅(gui),腈(jing)硅(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)等;按性能和用(yong)途的不(bu)同(tong)又可(ke)分(fen)(fen)(fen)為(wei)(wei)通用(yong)型(xing)(xing)(xing)、超耐低溫(wen)型(xing)(xing)(xing)、超耐高(gao)(gao)溫(wen)型(xing)(xing)(xing)、高(gao)(gao)強力型(xing)(xing)(xing)、耐油型(xing)(xing)(xing)、醫用(yong)型(xing)(xing)(xing)等等。
發展史(shi)
硅(gui)(gui)橡膠(jiao)(jiao)早(zao)期是由美國(guo)(guo)以三(san)氯(lv)化(hua)鐵(tie)為催化(hua)劑合(he)成(cheng)(cheng)的(de)。1945年,硅(gui)(gui)橡膠(jiao)(jiao)產(chan)品問世。1948年,采用(yong)高(gao)比表(biao)面積(ji)的(de)氣(qi)相法白炭黑補強的(de)硅(gui)(gui)橡膠(jiao)(jiao)研(yan)制成(cheng)(cheng)功,使(shi)硅(gui)(gui)橡膠(jiao)(jiao)的(de)性能躍升到(dao)(dao)實用(yong)階(jie)段,奠定了(le)現代(dai)硅(gui)(gui)橡膠(jiao)(jiao)生產(chan)技術的(de)基礎。從二甲基二氯(lv)硅(gui)(gui)烷合(he)成(cheng)(cheng)開(kai)始生產(chan)硅(gui)(gui)橡膠(jiao)(jiao)的(de)國(guo)(guo)家(jia)有美國(guo)(guo)。俄羅(luo)斯、德國(guo)(guo)、日本、韓國(guo)(guo)和中國(guo)(guo)等。中國(guo)(guo)硅(gui)(gui)橡膠(jiao)(jiao)的(de)工業化(hua)研(yan)究始于1957年,多家(jia)研(yan)究所和企業陸續(xu)開(kai)發(fa)出(chu)各種硅(gui)(gui)橡膠(jiao)(jiao)。到(dao)(dao)2003年底,中國(guo)(guo)硅(gui)(gui)橡膠(jiao)(jiao)生產(chan)能力為135千(qian)噸,其中高(gao)溫膠(jiao)(jiao)100千(qian)噸。
高溫(wen)硫化硅橡(xiang)膠
高溫硫(liu)(liu)化(hua)(hua)硅(gui)橡(xiang)膠(jiao)是(shi)指聚(ju)(ju)硅(gui)氧烷變成(cheng)(cheng)(cheng)彈性(xing)(xing)(xing)體的(de)(de)過程是(shi)經過高溫(110-170℃)硫(liu)(liu)化(hua)(hua)成(cheng)(cheng)(cheng)型的(de)(de)。它主要(yao)(yao)以高分子量的(de)(de)聚(ju)(ju)甲基乙烯基硅(gui)氧烷為生膠(jiao),混入補強填(tian)料、硫(liu)(liu)化(hua)(hua)劑(ji)(ji)等(deng),在加熱加壓下(xia)硫(liu)(liu)化(hua)(hua)成(cheng)(cheng)(cheng)彈性(xing)(xing)(xing)體。硅(gui)橡(xiang)膠(jiao)的(de)(de)補強主要(yao)(yao)是(shi)各(ge)種類(lei)型的(de)(de)白炭黑(hei),可使硫(liu)(liu)化(hua)(hua)膠(jiao)的(de)(de)強度(du)增加數十倍。有(you)時為了(le)降低成(cheng)(cheng)(cheng)本或改(gai)善膠(jiao)料性(xing)(xing)(xing)能(neng)(neng)及賦予硫(liu)(liu)化(hua)(hua)膠(jiao)各(ge)種特殊(shu)的(de)(de)性(xing)(xing)(xing)能(neng)(neng),也加入相應的(de)(de)各(ge)種添(tian)加劑(ji)(ji)。硫(liu)(liu)化(hua)(hua)劑(ji)(ji)是(shi)各(ge)種有(you)機過氧化(hua)(hua)物或加成(cheng)(cheng)(cheng)反應催化(hua)(hua)劑(ji)(ji)。
加工成型方法如圖所示(shi)。一次(ci)硫化(hua)的(de)(de)目的(de)(de)是進行(xing)高分子(zi)鏈的(de)(de)交(jiao)聯(lian)反應(ying);二次(ci)硫化(hua)的(de)(de)目的(de)(de)是進行(xing)補充(chong)交(jiao)聯(lian)、驅除硫化(hua)劑分解產物和其他揮發性(xing)化(hua)合物以(yi)穩定硫化(hua)膠(jiao)的(de)(de)各項(xiang)性(xing)能(neng)。常用的(de)(de)設備有開放式煉膠(jiao)機(ji)、捏合機(ji)及真空密煉機(ji)。
主要性能(neng)
(1)高(gao)溫(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)。硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)顯著的(de)(de)(de)(de)特(te)征是高(gao)溫(wen)(wen)穩定(ding)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing),雖然(ran)常溫(wen)(wen)下(xia)硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)的(de)(de)(de)(de)強度(du)僅是天(tian)然(ran)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)或某些合(he)成橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)的(de)(de)(de)(de)一半(ban),但在200℃以上的(de)(de)(de)(de)高(gao)溫(wen)(wen)環境下(xia),硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)仍能(neng)(neng)(neng)(neng)保持一定(ding)的(de)(de)(de)(de)柔韌性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)、回彈(dan)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)和表(biao)面硬度(du),且力(li)學(xue)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)無明(ming)顯變(bian)化(hua)(hua)(hua)。(2)低(di)溫(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)的(de)(de)(de)(de)玻璃化(hua)(hua)(hua)溫(wen)(wen)度(du)一般為(wei)-70~-50℃,特(te)殊配方可達(da)-100℃,表(biao)明(ming)其低(di)溫(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)優(you)異。這(zhe)對航空(kong)、宇航工(gong)業的(de)(de)(de)(de)意義重大。(3)耐(nai)候(hou)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)中(zhong)Si-O-Si鍵對氧(yang)、臭氧(yang)及(ji)紫(zi)外線等(deng)十分穩定(ding),在不(bu)加任何添加劑(ji)的(de)(de)(de)(de)情況下(xia),就具有優(you)良(liang)的(de)(de)(de)(de)耐(nai)候(hou)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)。(4)電(dian)(dian)氣(qi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)。硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)具有優(you)異的(de)(de)(de)(de)絕緣性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng),耐(nai)電(dian)(dian)暈性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)和耐(nai)電(dian)(dian)弧性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)也非(fei)常好。(5)物(wu)理機械性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)。硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)常溫(wen)(wen)下(xia)的(de)(de)(de)(de)物(wu)理機械性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)比通(tong)用(yong)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)差,但在150℃的(de)(de)(de)(de)高(gao)溫(wen)(wen)和-50℃的(de)(de)(de)(de)低(di)溫(wen)(wen)下(xia),其物(wu)理機械性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)優(you)于通(tong)用(yong)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)。(6)耐(nai)油及(ji)化(hua)(hua)(hua)學(xue)試劑(ji)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)。普通(tong)硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)具有中(zhong)等(deng)的(de)(de)(de)(de)耐(nai)油、耐(nai)溶劑(ji)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)。(7)氣(qi)體(ti)透(tou)過性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)。室溫(wen)(wen)下(xia)硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)對空(kong)氣(qi)、氮、氧(yang)、二氧(yang)化(hua)(hua)(hua)碳等(deng)氣(qi)體(ti)的(de)(de)(de)(de)透(tou)氣(qi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)比天(tian)然(ran)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)高(gao)出30-50倍。(8)生理惰(duo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)。硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)無毒,無味(wei),無嗅(xiu),與(yu)人(ren)體(ti)組(zu)織(zhi)不(bu)粘連,具有抗凝血作(zuo)用(yong),對肌體(ti)組(zu)織(zhi)的(de)(de)(de)(de)反應性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)非(fei)常少。特(te)別適合(he)作(zuo)為(wei)醫用(yong)材(cai)料。
硅橡膠(jiao)的用(yong)量
據中國(guo)汽(qi)車(che)(che)工(gong)(gong)業(ye)協會(hui)統計,2012年,汽(qi)車(che)(che)產(chan)銷(xiao)分(fen)別達到(dao)1927.18萬輛(liang)和1930.64萬輛(liang),同(tong)比分(fen)別增(zeng)長4.63%和4.33%,汽(qi)車(che)(che)工(gong)(gong)業(ye)硅橡膠(jiao)(jiao)的(de)(de)用量約(yue)達2.0萬t。根(gen)據觀研(yan)天下的(de)(de)新研(yan)究(jiu),增(zeng)加有(you)機硅材料在汽(qi)車(che)(che)零(ling)部(bu)件方面的(de)(de)用量,可(ke)以大(da)幅度(du)提(ti)高汽(qi)車(che)(che)的(de)(de)安全性(xing)能,因此,汽(qi)車(che)(che)產(chan)量和單車(che)(che)用量水平的(de)(de)提(ti)高都將推動(dong)汽(qi)車(che)(che)工(gong)(gong)業(ye)對硅橡膠(jiao)(jiao)需求的(de)(de)增(zeng)加。國(guo)家(jia)鼓勵自(zi)主品(pin)牌(pai)的(de)(de)汽(qi)車(che)(che)發展,關(guan)鍵汽(qi)車(che)(che)零(ling)部(bu)件實(shi)現自(zi)主化,《2012年度(du)黨政(zheng)機關(guan)公務用車(che)(che)選用車(che)(che)型目(mu)錄(征(zheng)求意見稿)》為自(zi)主品(pin)牌(pai)擴大(da)在政(zheng)府采購的(de)(de)市(shi)場份額,為改變(bian)目(mu)前國(guo)內(nei)政(zheng)府采購以合資品(pin)牌(pai)產(chan)品(pin)為主的(de)(de)局面提(ti)供(gong)了保障。促進(jin)自(zi)主品(pin)牌(pai)發展,國(guo)產(chan)汽(qi)車(che)(che)業(ye)的(de)(de)繁榮(rong)將為汽(qi)車(che)(che)膠(jiao)(jiao)的(de)(de)應用提(ti)供(gong)有(you)力保障。預測未來3年,我國(guo)室溫硫化硅橡膠(jiao)(jiao)在汽(qi)車(che)(che)行業(ye)將以年均20%增(zeng)長。
此外,硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)是重要的(de)(de)(de)非石(shi)(shi)油(you)基(ji)合(he)成(cheng)(cheng)橡(xiang)(xiang)膠(jiao),約占非石(shi)(shi)油(you)基(ji)合(he)成(cheng)(cheng)橡(xiang)(xiang)膠(jiao)消(xiao)費量的(de)(de)(de)98%。但因為(wei)(wei)石(shi)(shi)油(you)價格的(de)(de)(de)大幅上漲,同(tong)時(shi)我國在硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)的(de)(de)(de)關鍵原(yuan)料有(you)(you)(you)機(ji)硅(gui)(gui)(gui)(gui)單體的(de)(de)(de)生(sheng)產技(ji)術方面取得突破,有(you)(you)(you)機(ji)硅(gui)(gui)(gui)(gui)單體的(de)(de)(de)生(sheng)產技(ji)術在2005年前被幾(ji)家跨(kua)國公(gong)司壟斷,但目前我國已發(fa)展成(cheng)(cheng)為(wei)(wei)全球有(you)(you)(you)機(ji)硅(gui)(gui)(gui)(gui)單體第1大國,這2個方面原(yuan)因使硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)的(de)(de)(de)價格從(cong)2011年起開(kai)始低于石(shi)(shi)油(you)基(ji)合(he)成(cheng)(cheng)橡(xiang)(xiang)膠(jiao),僅約為(wei)(wei)大宗(zong)石(shi)(shi)油(you)基(ji)橡(xiang)(xiang)膠(jiao)的(de)(de)(de)80%~90%,成(cheng)(cheng)為(wei)(wei)廉(lian)價的(de)(de)(de)合(he)成(cheng)(cheng)橡(xiang)(xiang)膠(jiao),并開(kai)始大規(gui)模替代(dai)石(shi)(shi)油(you)基(ji)合(he)成(cheng)(cheng)橡(xiang)(xiang)膠(jiao)。這將極大拓展有(you)(you)(you)機(ji)硅(gui)(gui)(gui)(gui)產業(ye)的(de)(de)(de)市場(chang)空間,同(tong)時(shi)將帶動硅(gui)(gui)(gui)(gui)油(you)、硅(gui)(gui)(gui)(gui)烷偶(ou)聯劑(ji)和硅(gui)(gui)(gui)(gui)樹脂等其他有(you)(you)(you)機(ji)硅(gui)(gui)(gui)(gui)產品的(de)(de)(de)消(xiao)費。