硅橡膠是指(zhi)主(zhu)鏈由硅(gui)(gui)和(he)氧原(yuan)(yuan)子交(jiao)替構(gou)成,硅(gui)(gui)原(yuan)(yuan)子上通常連有兩個有機基(ji)團的(de)(de)(de)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)。普通的(de)(de)(de)硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)主(zhu)要由含(han)甲(jia)基(ji)和(he)少量乙烯基(ji)的(de)(de)(de)硅(gui)(gui)氧鏈節組成。苯基(ji)的(de)(de)(de)引入可提高(gao)硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)的(de)(de)(de)耐(nai)(nai)高(gao)、低溫性(xing)(xing)能,三氟丙基(ji)及氰基(ji)的(de)(de)(de)引入則可提高(gao)硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)的(de)(de)(de)耐(nai)(nai)溫及耐(nai)(nai)油性(xing)(xing)能。硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)耐(nai)(nai)低溫性(xing)(xing)能良好,一般(ban)在(zai)(zai)-55℃下仍能工作。引入苯基(ji)后(hou),可達-73℃。硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)的(de)(de)(de)耐(nai)(nai)熱(re)性(xing)(xing)能也很突出,在(zai)(zai)180℃下可長期工作,稍高(gao)于(yu)200℃也能承(cheng)受數周或更長時間(jian)仍有彈(dan)性(xing)(xing),瞬時可耐(nai)(nai)300℃以上的(de)(de)(de)高(gao)溫。硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)的(de)(de)(de)透(tou)氣(qi)性(xing)(xing)好,氧氣(qi)透(tou)過(guo)率(lv)在(zai)(zai)合成聚(ju)合物中是較高(gao)的(de)(de)(de)。此外,硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)還(huan)具有生(sheng)理(li)惰性(xing)(xing)、不會(hui)導致(zhi)凝血的(de)(de)(de)突出特性(xing)(xing),因此在(zai)(zai)醫用(yong)領域(yu)應用(yong)廣(guang)泛(fan)。
主要品種
硅(gui)(gui)橡膠(jiao)分(fen)(fen)類的(de)(de)方(fang)法很多,通(tong)常按(an)固化(hua)前的(de)(de)形態分(fen)(fen)為(wei)固體硅(gui)(gui)橡膠(jiao)和液體硅(gui)(gui)橡膠(jiao);按(an)硫化(hua)溫(wen)度(du)分(fen)(fen)為(wei)室溫(wen)硫化(hua)硅(gui)(gui)橡膠(jiao),高溫(wen)硫化(hua)硅(gui)(gui)橡膠(jiao);按(an)所用(yong)單體的(de)(de)不(bu)同(tong),可分(fen)(fen)為(wei)甲基乙烯(xi)基硅(gui)(gui)橡膠(jiao),甲基苯基乙烯(xi)基硅(gui)(gui)橡膠(jiao)、氟(fu)硅(gui)(gui),腈(jing)硅(gui)(gui)橡膠(jiao)等;按(an)性能和用(yong)途的(de)(de)不(bu)同(tong)又可分(fen)(fen)為(wei)通(tong)用(yong)型(xing)、超耐(nai)低溫(wen)型(xing)、超耐(nai)高溫(wen)型(xing)、高強力型(xing)、耐(nai)油型(xing)、醫用(yong)型(xing)等等。
發展史
硅橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)早(zao)期(qi)是(shi)由美(mei)國以三氯(lv)化(hua)鐵為(wei)(wei)催化(hua)劑合成(cheng)的(de)。1945年(nian),硅橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)產品問世(shi)。1948年(nian),采用高比表(biao)面積的(de)氣相法(fa)白炭黑(hei)補強(qiang)的(de)硅橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)研制(zhi)成(cheng)功(gong),使(shi)硅橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)的(de)性能(neng)躍(yue)升到(dao)(dao)實(shi)用階段,奠定了現代硅橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)生(sheng)(sheng)產技術的(de)基礎。從二甲基二氯(lv)硅烷合成(cheng)開(kai)始生(sheng)(sheng)產硅橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)的(de)國家(jia)有美(mei)國。俄羅(luo)斯、德(de)國、日本(ben)、韓國和(he)中(zhong)國等。中(zhong)國硅橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)的(de)工業(ye)化(hua)研究(jiu)始于1957年(nian),多家(jia)研究(jiu)所和(he)企業(ye)陸續開(kai)發出(chu)各種硅橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)。到(dao)(dao)2003年(nian)底,中(zhong)國硅橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)生(sheng)(sheng)產能(neng)力為(wei)(wei)135千(qian)噸,其中(zhong)高溫膠(jiao)(jiao)(jiao)(jiao)100千(qian)噸。
高溫硫化硅橡膠
高(gao)溫硫(liu)(liu)化(hua)硅橡膠是(shi)指聚硅氧(yang)烷(wan)變成(cheng)彈性(xing)體的(de)過程是(shi)經過高(gao)溫(110-170℃)硫(liu)(liu)化(hua)成(cheng)型(xing)的(de)。它(ta)主要以高(gao)分子(zi)量的(de)聚甲基乙烯基硅氧(yang)烷(wan)為(wei)生膠,混入補強填料、硫(liu)(liu)化(hua)劑等,在加(jia)(jia)(jia)熱加(jia)(jia)(jia)壓下硫(liu)(liu)化(hua)成(cheng)彈性(xing)體。硅橡膠的(de)補強主要是(shi)各種(zhong)類(lei)型(xing)的(de)白炭黑,可使硫(liu)(liu)化(hua)膠的(de)強度增加(jia)(jia)(jia)數(shu)十倍。有(you)時為(wei)了降(jiang)低成(cheng)本或(huo)(huo)改善膠料性(xing)能及賦予硫(liu)(liu)化(hua)膠各種(zhong)特殊的(de)性(xing)能,也加(jia)(jia)(jia)入相(xiang)應的(de)各種(zhong)添(tian)加(jia)(jia)(jia)劑。硫(liu)(liu)化(hua)劑是(shi)各種(zhong)有(you)機過氧(yang)化(hua)物或(huo)(huo)加(jia)(jia)(jia)成(cheng)反應催化(hua)劑。
加工成型(xing)方法如圖所(suo)示。一次硫化的(de)(de)目(mu)(mu)的(de)(de)是(shi)(shi)進行(xing)高分(fen)子鏈的(de)(de)交聯反應;二次硫化的(de)(de)目(mu)(mu)的(de)(de)是(shi)(shi)進行(xing)補(bu)充交聯、驅除硫化劑分(fen)解產(chan)物和其他揮(hui)發性(xing)化合(he)物以穩定(ding)硫化膠的(de)(de)各項(xiang)性(xing)能。常用的(de)(de)設備有開放式煉膠機、捏合(he)機及真空(kong)密煉機。
主要性能
(1)高溫性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)。硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)顯(xian)著的(de)特(te)征是(shi)高溫穩定(ding)性(xing)(xing)(xing)(xing)(xing)(xing)(xing),雖然(ran)常(chang)溫下(xia)(xia)(xia)硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)的(de)強度僅是(shi)天(tian)然(ran)橡(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)或某些合(he)成橡(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)的(de)一半,但在200℃以(yi)上(shang)的(de)高溫環(huan)境下(xia)(xia)(xia),硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)仍(reng)能(neng)(neng)(neng)(neng)保持一定(ding)的(de)柔(rou)韌性(xing)(xing)(xing)(xing)(xing)(xing)(xing)、回彈(dan)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)和(he)(he)表(biao)(biao)面硬(ying)度,且力(li)學性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)無(wu)(wu)明顯(xian)變化。(2)低溫性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)的(de)玻璃化溫度一般為(wei)-70~-50℃,特(te)殊(shu)配(pei)方可達-100℃,表(biao)(biao)明其低溫性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)優異。這(zhe)對(dui)(dui)航(hang)(hang)空、宇(yu)航(hang)(hang)工(gong)業的(de)意義重(zhong)大。(3)耐(nai)(nai)候性(xing)(xing)(xing)(xing)(xing)(xing)(xing)硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)中(zhong)Si-O-Si鍵對(dui)(dui)氧、臭(chou)氧及紫外(wai)線等(deng)(deng)十分穩定(ding),在不加(jia)(jia)任何添(tian)加(jia)(jia)劑(ji)的(de)情況下(xia)(xia)(xia),就具(ju)有(you)(you)優良(liang)的(de)耐(nai)(nai)候性(xing)(xing)(xing)(xing)(xing)(xing)(xing)。(4)電氣(qi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)。硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)具(ju)有(you)(you)優異的(de)絕(jue)緣性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng),耐(nai)(nai)電暈性(xing)(xing)(xing)(xing)(xing)(xing)(xing)和(he)(he)耐(nai)(nai)電弧性(xing)(xing)(xing)(xing)(xing)(xing)(xing)也非(fei)常(chang)好。(5)物(wu)理機械性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)。硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)常(chang)溫下(xia)(xia)(xia)的(de)物(wu)理機械性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)比通用橡(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)差,但在150℃的(de)高溫和(he)(he)-50℃的(de)低溫下(xia)(xia)(xia),其物(wu)理機械性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)優于通用橡(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)。(6)耐(nai)(nai)油(you)及化學試劑(ji)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)。普通硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)具(ju)有(you)(you)中(zhong)等(deng)(deng)的(de)耐(nai)(nai)油(you)、耐(nai)(nai)溶(rong)劑(ji)性(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)能(neng)(neng)(neng)(neng)。室(shi)溫下(xia)(xia)(xia)硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)對(dui)(dui)空氣(qi)、氮、氧、二氧化碳等(deng)(deng)氣(qi)體(ti)的(de)透(tou)氣(qi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)比天(tian)然(ran)橡(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)高出30-50倍(bei)。(8)生理惰性(xing)(xing)(xing)(xing)(xing)(xing)(xing)。硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)無(wu)(wu)毒(du),無(wu)(wu)味,無(wu)(wu)嗅(xiu),與人體(ti)組(zu)織(zhi)不粘(zhan)連(lian),具(ju)有(you)(you)抗凝血作用,對(dui)(dui)肌體(ti)組(zu)織(zhi)的(de)反應性(xing)(xing)(xing)(xing)(xing)(xing)(xing)非(fei)常(chang)少(shao)。特(te)別(bie)適合(he)作為(wei)醫用材料。
硅橡膠的用量
據中(zhong)國(guo)汽(qi)(qi)(qi)(qi)(qi)(qi)車(che)(che)工業(ye)協(xie)會統計,2012年(nian)(nian),汽(qi)(qi)(qi)(qi)(qi)(qi)車(che)(che)產(chan)(chan)銷(xiao)分別(bie)達到1927.18萬(wan)(wan)輛(liang)和1930.64萬(wan)(wan)輛(liang),同(tong)比分別(bie)增(zeng)長(chang)4.63%和4.33%,汽(qi)(qi)(qi)(qi)(qi)(qi)車(che)(che)工業(ye)硅(gui)(gui)橡(xiang)(xiang)膠(jiao)的(de)用(yong)(yong)(yong)量約達2.0萬(wan)(wan)t。根據觀研天(tian)下的(de)新研究,增(zeng)加有機硅(gui)(gui)材料在汽(qi)(qi)(qi)(qi)(qi)(qi)車(che)(che)零部件方面(mian)的(de)用(yong)(yong)(yong)量,可以大幅度(du)(du)提(ti)高(gao)汽(qi)(qi)(qi)(qi)(qi)(qi)車(che)(che)的(de)安全(quan)性(xing)能,因此,汽(qi)(qi)(qi)(qi)(qi)(qi)車(che)(che)產(chan)(chan)量和單車(che)(che)用(yong)(yong)(yong)量水平的(de)提(ti)高(gao)都(dou)將(jiang)推動汽(qi)(qi)(qi)(qi)(qi)(qi)車(che)(che)工業(ye)對硅(gui)(gui)橡(xiang)(xiang)膠(jiao)需求的(de)增(zeng)加。國(guo)家鼓勵自(zi)主品(pin)(pin)牌(pai)的(de)汽(qi)(qi)(qi)(qi)(qi)(qi)車(che)(che)發(fa)展,關(guan)鍵汽(qi)(qi)(qi)(qi)(qi)(qi)車(che)(che)零部件實現(xian)自(zi)主化,《2012年(nian)(nian)度(du)(du)黨政(zheng)(zheng)機關(guan)公務用(yong)(yong)(yong)車(che)(che)選用(yong)(yong)(yong)車(che)(che)型目(mu)錄(征求意(yi)見稿)》為自(zi)主品(pin)(pin)牌(pai)擴大在政(zheng)(zheng)府(fu)采購的(de)市場份額,為改變(bian)目(mu)前國(guo)內政(zheng)(zheng)府(fu)采購以合資品(pin)(pin)牌(pai)產(chan)(chan)品(pin)(pin)為主的(de)局面(mian)提(ti)供了保(bao)障。促(cu)進自(zi)主品(pin)(pin)牌(pai)發(fa)展,國(guo)產(chan)(chan)汽(qi)(qi)(qi)(qi)(qi)(qi)車(che)(che)業(ye)的(de)繁榮將(jiang)為汽(qi)(qi)(qi)(qi)(qi)(qi)車(che)(che)膠(jiao)的(de)應用(yong)(yong)(yong)提(ti)供有力(li)保(bao)障。預測未來3年(nian)(nian),我國(guo)室(shi)溫硫化硅(gui)(gui)橡(xiang)(xiang)膠(jiao)在汽(qi)(qi)(qi)(qi)(qi)(qi)車(che)(che)行業(ye)將(jiang)以年(nian)(nian)均20%增(zeng)長(chang)。
此外,硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)是重(zhong)要的(de)(de)(de)非石(shi)油基合(he)成(cheng)(cheng)橡(xiang)(xiang)(xiang)(xiang)膠(jiao),約(yue)占非石(shi)油基合(he)成(cheng)(cheng)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)消費量的(de)(de)(de)98%。但因為石(shi)油價格的(de)(de)(de)大幅上漲(zhang),同(tong)時我(wo)國(guo)在(zai)硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)的(de)(de)(de)關鍵原料(liao)有(you)機(ji)硅(gui)(gui)(gui)(gui)單(dan)體(ti)的(de)(de)(de)生(sheng)產(chan)(chan)技術方面取得突破,有(you)機(ji)硅(gui)(gui)(gui)(gui)單(dan)體(ti)的(de)(de)(de)生(sheng)產(chan)(chan)技術在(zai)2005年前(qian)被幾(ji)家跨國(guo)公司壟(long)斷,但目前(qian)我(wo)國(guo)已發(fa)展(zhan)成(cheng)(cheng)為全球有(you)機(ji)硅(gui)(gui)(gui)(gui)單(dan)體(ti)第(di)1大國(guo),這(zhe)(zhe)2個(ge)方面原因使硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)的(de)(de)(de)價格從2011年起開始低(di)于(yu)石(shi)油基合(he)成(cheng)(cheng)橡(xiang)(xiang)(xiang)(xiang)膠(jiao),僅約(yue)為大宗石(shi)油基橡(xiang)(xiang)(xiang)(xiang)膠(jiao)的(de)(de)(de)80%~90%,成(cheng)(cheng)為廉價的(de)(de)(de)合(he)成(cheng)(cheng)橡(xiang)(xiang)(xiang)(xiang)膠(jiao),并開始大規模替代石(shi)油基合(he)成(cheng)(cheng)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)。這(zhe)(zhe)將極大拓展(zhan)有(you)機(ji)硅(gui)(gui)(gui)(gui)產(chan)(chan)業的(de)(de)(de)市場空間,同(tong)時將帶動硅(gui)(gui)(gui)(gui)油、硅(gui)(gui)(gui)(gui)烷偶聯劑(ji)和硅(gui)(gui)(gui)(gui)樹脂等其他(ta)有(you)機(ji)硅(gui)(gui)(gui)(gui)產(chan)(chan)品的(de)(de)(de)消費。