
硅橡膠是指主(zhu)鏈由硅(gui)(gui)和氧原子交替構成,硅(gui)(gui)原子上通常連有(you)兩個(ge)有(you)機基(ji)(ji)團的(de)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)。普通的(de)硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)主(zhu)要由含(han)甲基(ji)(ji)和少量乙烯基(ji)(ji)的(de)硅(gui)(gui)氧鏈節(jie)組成。苯基(ji)(ji)的(de)引(yin)入(ru)(ru)可(ke)(ke)提(ti)(ti)高(gao)硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)的(de)耐(nai)高(gao)、低溫性(xing)能,三氟丙(bing)基(ji)(ji)及(ji)氰基(ji)(ji)的(de)引(yin)入(ru)(ru)則可(ke)(ke)提(ti)(ti)高(gao)硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)的(de)耐(nai)溫及(ji)耐(nai)油(you)性(xing)能。硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)耐(nai)低溫性(xing)能良好,一般在(zai)-55℃下仍(reng)能工作。引(yin)入(ru)(ru)苯基(ji)(ji)后,可(ke)(ke)達-73℃。硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)的(de)耐(nai)熱性(xing)能也很突(tu)出(chu),在(zai)180℃下可(ke)(ke)長期工作,稍高(gao)于200℃也能承受數(shu)周或更(geng)長時間(jian)仍(reng)有(you)彈性(xing),瞬時可(ke)(ke)耐(nai)300℃以上的(de)高(gao)溫。硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)的(de)透氣性(xing)好,氧氣透過(guo)率在(zai)合(he)成聚合(he)物中是較高(gao)的(de)。此(ci)外,硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)還具有(you)生理惰性(xing)、不會導致(zhi)凝血的(de)突(tu)出(chu)特性(xing),因此(ci)在(zai)醫用領域應(ying)用廣泛。
主要品種
硅(gui)(gui)(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)分(fen)類(lei)的(de)方法很多,通常按固化(hua)(hua)前的(de)形態分(fen)為(wei)固體(ti)硅(gui)(gui)(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)和液體(ti)硅(gui)(gui)(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao);按硫化(hua)(hua)溫(wen)度分(fen)為(wei)室溫(wen)硫化(hua)(hua)硅(gui)(gui)(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao),高(gao)溫(wen)硫化(hua)(hua)硅(gui)(gui)(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao);按所用(yong)單體(ti)的(de)不同,可分(fen)為(wei)甲(jia)基(ji)(ji)乙烯(xi)基(ji)(ji)硅(gui)(gui)(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao),甲(jia)基(ji)(ji)苯基(ji)(ji)乙烯(xi)基(ji)(ji)硅(gui)(gui)(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)、氟硅(gui)(gui)(gui)(gui)(gui),腈硅(gui)(gui)(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)等;按性(xing)能和用(yong)途的(de)不同又可分(fen)為(wei)通用(yong)型(xing)(xing)、超(chao)耐低溫(wen)型(xing)(xing)、超(chao)耐高(gao)溫(wen)型(xing)(xing)、高(gao)強(qiang)力型(xing)(xing)、耐油型(xing)(xing)、醫用(yong)型(xing)(xing)等等。
發展史
硅(gui)(gui)橡(xiang)膠(jiao)(jiao)早期是由美國(guo)(guo)以三氯(lv)化(hua)(hua)鐵為(wei)催化(hua)(hua)劑(ji)合成(cheng)的(de)(de)。1945年,硅(gui)(gui)橡(xiang)膠(jiao)(jiao)產品問世。1948年,采(cai)用高比表面積的(de)(de)氣相(xiang)法(fa)白炭黑補強的(de)(de)硅(gui)(gui)橡(xiang)膠(jiao)(jiao)研(yan)制成(cheng)功(gong),使硅(gui)(gui)橡(xiang)膠(jiao)(jiao)的(de)(de)性能躍升到實(shi)用階段,奠定了現(xian)代(dai)硅(gui)(gui)橡(xiang)膠(jiao)(jiao)生(sheng)產技術的(de)(de)基(ji)礎(chu)。從(cong)二(er)甲基(ji)二(er)氯(lv)硅(gui)(gui)烷合成(cheng)開始生(sheng)產硅(gui)(gui)橡(xiang)膠(jiao)(jiao)的(de)(de)國(guo)(guo)家有美國(guo)(guo)。俄羅斯、德國(guo)(guo)、日(ri)本、韓國(guo)(guo)和中(zhong)國(guo)(guo)等。中(zhong)國(guo)(guo)硅(gui)(gui)橡(xiang)膠(jiao)(jiao)的(de)(de)工業化(hua)(hua)研(yan)究(jiu)始于(yu)1957年,多家研(yan)究(jiu)所和企(qi)業陸續開發出各種硅(gui)(gui)橡(xiang)膠(jiao)(jiao)。到2003年底,中(zhong)國(guo)(guo)硅(gui)(gui)橡(xiang)膠(jiao)(jiao)生(sheng)產能力為(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)化硅(gui)(gui)橡膠(jiao)(jiao)(jiao)是(shi)指(zhi)聚硅(gui)(gui)氧烷(wan)變(bian)成(cheng)彈(dan)性體(ti)的(de)(de)(de)(de)過程(cheng)是(shi)經(jing)過高(gao)溫(110-170℃)硫(liu)(liu)化成(cheng)型的(de)(de)(de)(de)。它主(zhu)要以高(gao)分子量(liang)的(de)(de)(de)(de)聚甲基乙烯基硅(gui)(gui)氧烷(wan)為(wei)生膠(jiao)(jiao)(jiao),混入(ru)補強(qiang)填(tian)料(liao)(liao)、硫(liu)(liu)化劑(ji)等,在加(jia)(jia)熱加(jia)(jia)壓下硫(liu)(liu)化成(cheng)彈(dan)性體(ti)。硅(gui)(gui)橡膠(jiao)(jiao)(jiao)的(de)(de)(de)(de)補強(qiang)主(zhu)要是(shi)各(ge)種(zhong)類(lei)型的(de)(de)(de)(de)白炭黑,可使(shi)硫(liu)(liu)化膠(jiao)(jiao)(jiao)的(de)(de)(de)(de)強(qiang)度(du)增加(jia)(jia)數十(shi)倍。有時為(wei)了降低成(cheng)本或改善膠(jiao)(jiao)(jiao)料(liao)(liao)性能(neng)及賦予硫(liu)(liu)化膠(jiao)(jiao)(jiao)各(ge)種(zhong)特殊的(de)(de)(de)(de)性能(neng),也加(jia)(jia)入(ru)相(xiang)應的(de)(de)(de)(de)各(ge)種(zhong)添加(jia)(jia)劑(ji)。硫(liu)(liu)化劑(ji)是(shi)各(ge)種(zhong)有機過氧化物或加(jia)(jia)成(cheng)反應催化劑(ji)。
加工成(cheng)型方法如(ru)圖(tu)所示。一次硫化(hua)(hua)的(de)目(mu)的(de)是(shi)進行(xing)高分(fen)子鏈的(de)交(jiao)聯反應(ying);二(er)次硫化(hua)(hua)的(de)目(mu)的(de)是(shi)進行(xing)補充交(jiao)聯、驅除硫化(hua)(hua)劑分(fen)解(jie)產物(wu)和其他揮發性化(hua)(hua)合物(wu)以穩定硫化(hua)(hua)膠(jiao)的(de)各項(xiang)性能(neng)。常用的(de)設(she)備有開放式煉(lian)膠(jiao)機(ji)(ji)、捏合機(ji)(ji)及真空密(mi)煉(lian)機(ji)(ji)。
主要性能
(1)高(gao)溫(wen)(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)。硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)顯著的(de)(de)(de)特(te)征是高(gao)溫(wen)(wen)(wen)穩(wen)定性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing),雖然(ran)常(chang)溫(wen)(wen)(wen)下硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)的(de)(de)(de)強度僅(jin)是天然(ran)橡(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)或某些(xie)合成橡(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)的(de)(de)(de)一(yi)半,但在200℃以上的(de)(de)(de)高(gao)溫(wen)(wen)(wen)環(huan)境下,硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)仍能(neng)(neng)保(bao)持(chi)一(yi)定的(de)(de)(de)柔韌性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)、回彈(dan)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)和表面硬度,且力(li)學性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)無(wu)明顯變化(hua)。(2)低溫(wen)(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)的(de)(de)(de)玻璃(li)化(hua)溫(wen)(wen)(wen)度一(yi)般為-70~-50℃,特(te)殊配方可達-100℃,表明其低溫(wen)(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)優(you)(you)(you)異。這對(dui)(dui)航空、宇航工業(ye)的(de)(de)(de)意義(yi)重(zhong)大(da)。(3)耐(nai)(nai)候(hou)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)中Si-O-Si鍵對(dui)(dui)氧(yang)、臭(chou)氧(yang)及紫(zi)外線等(deng)(deng)十分穩(wen)定,在不加(jia)任何(he)添(tian)加(jia)劑(ji)(ji)(ji)的(de)(de)(de)情況(kuang)下,就具(ju)有優(you)(you)(you)良的(de)(de)(de)耐(nai)(nai)候(hou)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)。(4)電氣(qi)(qi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)。硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)具(ju)有優(you)(you)(you)異的(de)(de)(de)絕緣(yuan)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng),耐(nai)(nai)電暈性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)和耐(nai)(nai)電弧性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)也非(fei)常(chang)好。(5)物(wu)理(li)(li)機(ji)械(xie)(xie)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)。硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)常(chang)溫(wen)(wen)(wen)下的(de)(de)(de)物(wu)理(li)(li)機(ji)械(xie)(xie)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)比通(tong)用(yong)橡(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)差(cha),但在150℃的(de)(de)(de)高(gao)溫(wen)(wen)(wen)和-50℃的(de)(de)(de)低溫(wen)(wen)(wen)下,其物(wu)理(li)(li)機(ji)械(xie)(xie)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)優(you)(you)(you)于通(tong)用(yong)橡(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)。(6)耐(nai)(nai)油(you)(you)及化(hua)學試劑(ji)(ji)(ji)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)。普通(tong)硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)具(ju)有中等(deng)(deng)的(de)(de)(de)耐(nai)(nai)油(you)(you)、耐(nai)(nai)溶劑(ji)(ji)(ji)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)。(7)氣(qi)(qi)體透過性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)。室(shi)溫(wen)(wen)(wen)下硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)對(dui)(dui)空氣(qi)(qi)、氮、氧(yang)、二氧(yang)化(hua)碳等(deng)(deng)氣(qi)(qi)體的(de)(de)(de)透氣(qi)(qi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)比天然(ran)橡(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)高(gao)出30-50倍(bei)。(8)生(sheng)理(li)(li)惰性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)。硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)無(wu)毒(du),無(wu)味,無(wu)嗅,與人體組織(zhi)(zhi)不粘(zhan)連,具(ju)有抗凝血作(zuo)用(yong),對(dui)(dui)肌體組織(zhi)(zhi)的(de)(de)(de)反應(ying)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)非(fei)常(chang)少。特(te)別適合作(zuo)為醫用(yong)材料。
硅橡膠的用量
據(ju)(ju)中國(guo)汽(qi)(qi)車(che)工業(ye)協(xie)會統計,2012年,汽(qi)(qi)車(che)產(chan)(chan)銷(xiao)分別達到1927.18萬(wan)輛(liang)和(he)1930.64萬(wan)輛(liang),同(tong)比分別增(zeng)(zeng)長4.63%和(he)4.33%,汽(qi)(qi)車(che)工業(ye)硅橡膠(jiao)(jiao)的用量約達2.0萬(wan)t。根據(ju)(ju)觀(guan)研(yan)天下的新研(yan)究,增(zeng)(zeng)加有(you)機硅材料在(zai)汽(qi)(qi)車(che)零(ling)部件方面(mian)的用量,可(ke)以大幅度提高汽(qi)(qi)車(che)的安(an)全性能,因此,汽(qi)(qi)車(che)產(chan)(chan)量和(he)單車(che)用量水平的提高都將推動汽(qi)(qi)車(che)工業(ye)對硅橡膠(jiao)(jiao)需求的增(zeng)(zeng)加。國(guo)家鼓(gu)勵自(zi)(zi)主(zhu)品(pin)(pin)牌的汽(qi)(qi)車(che)發展(zhan),關鍵汽(qi)(qi)車(che)零(ling)部件實現自(zi)(zi)主(zhu)化(hua),《2012年度黨政機關公(gong)務用車(che)選(xuan)用車(che)型目(mu)錄(征求意見稿(gao))》為自(zi)(zi)主(zhu)品(pin)(pin)牌擴大在(zai)政府(fu)采購的市場份額(e),為改變目(mu)前(qian)國(guo)內政府(fu)采購以合資品(pin)(pin)牌產(chan)(chan)品(pin)(pin)為主(zhu)的局面(mian)提供了(le)保障。促進(jin)自(zi)(zi)主(zhu)品(pin)(pin)牌發展(zhan),國(guo)產(chan)(chan)汽(qi)(qi)車(che)業(ye)的繁榮將為汽(qi)(qi)車(che)膠(jiao)(jiao)的應用提供有(you)力保障。預測(ce)未來3年,我國(guo)室溫硫化(hua)硅橡膠(jiao)(jiao)在(zai)汽(qi)(qi)車(che)行業(ye)將以年均(jun)20%增(zeng)(zeng)長。
此外,硅橡膠(jiao)(jiao)(jiao)是重要的(de)(de)(de)(de)非石(shi)(shi)油基(ji)合(he)成橡膠(jiao)(jiao)(jiao),約占(zhan)非石(shi)(shi)油基(ji)合(he)成橡膠(jiao)(jiao)(jiao)消費量的(de)(de)(de)(de)98%。但(dan)因為石(shi)(shi)油價(jia)格的(de)(de)(de)(de)大(da)幅(fu)上漲(zhang),同(tong)時我國在硅橡膠(jiao)(jiao)(jiao)的(de)(de)(de)(de)關鍵原料有(you)(you)機硅單體的(de)(de)(de)(de)生產(chan)(chan)技(ji)術方面取得突破,有(you)(you)機硅單體的(de)(de)(de)(de)生產(chan)(chan)技(ji)術在2005年(nian)前被(bei)幾家跨國公(gong)司(si)壟斷,但(dan)目前我國已發展(zhan)成為全球(qiu)有(you)(you)機硅單體第(di)1大(da)國,這(zhe)2個方面原因使硅橡膠(jiao)(jiao)(jiao)的(de)(de)(de)(de)價(jia)格從2011年(nian)起開(kai)始低于(yu)石(shi)(shi)油基(ji)合(he)成橡膠(jiao)(jiao)(jiao),僅(jin)約為大(da)宗(zong)石(shi)(shi)油基(ji)橡膠(jiao)(jiao)(jiao)的(de)(de)(de)(de)80%~90%,成為廉價(jia)的(de)(de)(de)(de)合(he)成橡膠(jiao)(jiao)(jiao),并開(kai)始大(da)規(gui)模替代(dai)石(shi)(shi)油基(ji)合(he)成橡膠(jiao)(jiao)(jiao)。這(zhe)將極大(da)拓(tuo)展(zhan)有(you)(you)機硅產(chan)(chan)業的(de)(de)(de)(de)市場(chang)空間,同(tong)時將帶動(dong)硅油、硅烷(wan)偶(ou)聯劑和硅樹脂等其他有(you)(you)機硅產(chan)(chan)品(pin)的(de)(de)(de)(de)消費。