
硅橡膠是指主鏈(lian)由(you)硅(gui)和氧原子交替構(gou)成(cheng)(cheng),硅(gui)原子上通常連有兩個有機(ji)基(ji)團的(de)(de)(de)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)。普通的(de)(de)(de)硅(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)主要(yao)由(you)含甲基(ji)和少量乙烯基(ji)的(de)(de)(de)硅(gui)氧鏈(lian)節組成(cheng)(cheng)。苯基(ji)的(de)(de)(de)引入(ru)(ru)可提高(gao)(gao)硅(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)的(de)(de)(de)耐(nai)高(gao)(gao)、低溫性能(neng),三氟(fu)丙基(ji)及氰基(ji)的(de)(de)(de)引入(ru)(ru)則可提高(gao)(gao)硅(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)的(de)(de)(de)耐(nai)溫及耐(nai)油性能(neng)。硅(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)耐(nai)低溫性能(neng)良好,一般在-55℃下(xia)仍能(neng)工作。引入(ru)(ru)苯基(ji)后,可達-73℃。硅(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)的(de)(de)(de)耐(nai)熱性能(neng)也(ye)(ye)很突出(chu),在180℃下(xia)可長期工作,稍(shao)高(gao)(gao)于(yu)200℃也(ye)(ye)能(neng)承受數(shu)周或更長時間仍有彈性,瞬時可耐(nai)300℃以上的(de)(de)(de)高(gao)(gao)溫。硅(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)的(de)(de)(de)透(tou)(tou)氣(qi)性好,氧氣(qi)透(tou)(tou)過率在合成(cheng)(cheng)聚合物中是較高(gao)(gao)的(de)(de)(de)。此外(wai),硅(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)還具有生理惰性、不會導致凝血的(de)(de)(de)突出(chu)特(te)性,因此在醫用領域(yu)應用廣泛(fan)。
主要品種
硅(gui)(gui)橡膠(jiao)(jiao)(jiao)(jiao)(jiao)分(fen)類的方法很多,通常按固(gu)(gu)化(hua)(hua)前的形(xing)態分(fen)為(wei)(wei)固(gu)(gu)體(ti)硅(gui)(gui)橡膠(jiao)(jiao)(jiao)(jiao)(jiao)和液體(ti)硅(gui)(gui)橡膠(jiao)(jiao)(jiao)(jiao)(jiao);按硫(liu)化(hua)(hua)溫(wen)度(du)分(fen)為(wei)(wei)室(shi)溫(wen)硫(liu)化(hua)(hua)硅(gui)(gui)橡膠(jiao)(jiao)(jiao)(jiao)(jiao),高(gao)溫(wen)硫(liu)化(hua)(hua)硅(gui)(gui)橡膠(jiao)(jiao)(jiao)(jiao)(jiao);按所用單(dan)體(ti)的不(bu)同(tong),可分(fen)為(wei)(wei)甲基(ji)乙烯基(ji)硅(gui)(gui)橡膠(jiao)(jiao)(jiao)(jiao)(jiao),甲基(ji)苯基(ji)乙烯基(ji)硅(gui)(gui)橡膠(jiao)(jiao)(jiao)(jiao)(jiao)、氟硅(gui)(gui),腈(jing)硅(gui)(gui)橡膠(jiao)(jiao)(jiao)(jiao)(jiao)等(deng);按性能和用途的不(bu)同(tong)又可分(fen)為(wei)(wei)通用型(xing)、超(chao)耐低(di)溫(wen)型(xing)、超(chao)耐高(gao)溫(wen)型(xing)、高(gao)強力(li)型(xing)、耐油型(xing)、醫(yi)用型(xing)等(deng)等(deng)。
發展史
硅(gui)(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)早期是由(you)美國(guo)(guo)以三氯化(hua)鐵(tie)為催化(hua)劑合成(cheng)的(de)(de)。1945年(nian),硅(gui)(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)產品問世。1948年(nian),采用高比表面積的(de)(de)氣相(xiang)法白炭(tan)黑補(bu)強(qiang)的(de)(de)硅(gui)(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)研(yan)(yan)制成(cheng)功(gong),使硅(gui)(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)的(de)(de)性能躍升到實(shi)用階段,奠定(ding)了現(xian)代(dai)硅(gui)(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)生產技術的(de)(de)基(ji)礎。從二(er)甲(jia)基(ji)二(er)氯硅(gui)(gui)(gui)(gui)(gui)烷合成(cheng)開(kai)始(shi)生產硅(gui)(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)的(de)(de)國(guo)(guo)家(jia)有美國(guo)(guo)。俄羅斯、德國(guo)(guo)、日本、韓國(guo)(guo)和(he)中國(guo)(guo)等。中國(guo)(guo)硅(gui)(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)的(de)(de)工(gong)業化(hua)研(yan)(yan)究始(shi)于1957年(nian),多家(jia)研(yan)(yan)究所和(he)企業陸續(xu)開(kai)發出各種硅(gui)(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)。到2003年(nian)底,中國(guo)(guo)硅(gui)(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)生產能力為135千噸,其(qi)中高溫膠(jiao)(jiao)(jiao)100千噸。
高溫硫化硅橡膠
高溫(wen)硫(liu)(liu)化(hua)硅(gui)橡膠(jiao)是指聚硅(gui)氧烷變(bian)成(cheng)彈性體的(de)(de)過程是經(jing)過高溫(wen)(110-170℃)硫(liu)(liu)化(hua)成(cheng)型的(de)(de)。它主要以高分子量的(de)(de)聚甲基(ji)乙烯基(ji)硅(gui)氧烷為生膠(jiao),混入補強(qiang)填料(liao)、硫(liu)(liu)化(hua)劑等,在加(jia)熱加(jia)壓下硫(liu)(liu)化(hua)成(cheng)彈性體。硅(gui)橡膠(jiao)的(de)(de)補強(qiang)主要是各(ge)種(zhong)類型的(de)(de)白炭黑,可使(shi)硫(liu)(liu)化(hua)膠(jiao)的(de)(de)強(qiang)度增加(jia)數十倍。有時為了降低成(cheng)本或改善(shan)膠(jiao)料(liao)性能及(ji)賦予硫(liu)(liu)化(hua)膠(jiao)各(ge)種(zhong)特殊的(de)(de)性能,也加(jia)入相應的(de)(de)各(ge)種(zhong)添加(jia)劑。硫(liu)(liu)化(hua)劑是各(ge)種(zhong)有機(ji)過氧化(hua)物(wu)或加(jia)成(cheng)反應催化(hua)劑。
加(jia)工成(cheng)型方(fang)法如圖所(suo)示。一次(ci)硫(liu)(liu)(liu)化(hua)的目的是進行(xing)高(gao)分子(zi)鏈的交聯反應;二次(ci)硫(liu)(liu)(liu)化(hua)的目的是進行(xing)補充交聯、驅(qu)除硫(liu)(liu)(liu)化(hua)劑分解產物和(he)其他揮(hui)發性(xing)化(hua)合(he)物以(yi)穩定硫(liu)(liu)(liu)化(hua)膠(jiao)的各項性(xing)能。常用的設備有(you)開放(fang)式煉膠(jiao)機(ji)、捏合(he)機(ji)及(ji)真空密煉機(ji)。
主要性能
(1)高(gao)(gao)溫(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)。硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)顯著的(de)(de)特征(zheng)是(shi)高(gao)(gao)溫(wen)穩定性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing),雖然常(chang)溫(wen)下(xia)硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)的(de)(de)強度(du)僅是(shi)天然橡(xiang)(xiang)(xiang)膠(jiao)(jiao)或某些合成橡(xiang)(xiang)(xiang)膠(jiao)(jiao)的(de)(de)一(yi)半,但(dan)(dan)在200℃以上的(de)(de)高(gao)(gao)溫(wen)環(huan)境下(xia),硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)仍能(neng)(neng)(neng)(neng)(neng)保(bao)持一(yi)定的(de)(de)柔韌性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)、回彈性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)和(he)(he)表面硬度(du),且力(li)學性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)無(wu)明顯變化(hua)(hua)。(2)低溫(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)的(de)(de)玻璃(li)化(hua)(hua)溫(wen)度(du)一(yi)般為-70~-50℃,特殊配方(fang)可(ke)達(da)-100℃,表明其(qi)低溫(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)優(you)異。這對(dui)(dui)航(hang)空、宇航(hang)工業的(de)(de)意義重大(da)。(3)耐(nai)候(hou)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)中Si-O-Si鍵對(dui)(dui)氧、臭(chou)氧及紫(zi)外線等十分(fen)穩定,在不加任(ren)何添加劑(ji)的(de)(de)情(qing)況下(xia),就具有(you)優(you)良的(de)(de)耐(nai)候(hou)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)。(4)電氣(qi)(qi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)。硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)具有(you)優(you)異的(de)(de)絕(jue)緣性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng),耐(nai)電暈性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)和(he)(he)耐(nai)電弧(hu)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)也非常(chang)好。(5)物理(li)機(ji)械(xie)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)。硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)常(chang)溫(wen)下(xia)的(de)(de)物理(li)機(ji)械(xie)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)比通(tong)用(yong)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)差,但(dan)(dan)在150℃的(de)(de)高(gao)(gao)溫(wen)和(he)(he)-50℃的(de)(de)低溫(wen)下(xia),其(qi)物理(li)機(ji)械(xie)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)優(you)于通(tong)用(yong)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)。(6)耐(nai)油(you)及化(hua)(hua)學試劑(ji)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)。普(pu)通(tong)硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)具有(you)中等的(de)(de)耐(nai)油(you)、耐(nai)溶劑(ji)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)。(7)氣(qi)(qi)體透過(guo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)。室溫(wen)下(xia)硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)對(dui)(dui)空氣(qi)(qi)、氮、氧、二氧化(hua)(hua)碳等氣(qi)(qi)體的(de)(de)透氣(qi)(qi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)比天然橡(xiang)(xiang)(xiang)膠(jiao)(jiao)高(gao)(gao)出30-50倍。(8)生(sheng)理(li)惰性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)。硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)無(wu)毒(du),無(wu)味,無(wu)嗅(xiu),與人體組(zu)織(zhi)不粘(zhan)連,具有(you)抗凝血作用(yong),對(dui)(dui)肌體組(zu)織(zhi)的(de)(de)反應性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)非常(chang)少。特別適合作為醫用(yong)材料。
硅橡膠的用量
據(ju)中國(guo)汽(qi)車工(gong)業協(xie)會統計,2012年(nian)(nian),汽(qi)車產銷分別達到1927.18萬(wan)(wan)輛和1930.64萬(wan)(wan)輛,同比分別增長4.63%和4.33%,汽(qi)車工(gong)業硅(gui)橡(xiang)膠(jiao)的(de)(de)(de)(de)用(yong)(yong)(yong)量約達2.0萬(wan)(wan)t。根據(ju)觀研天下的(de)(de)(de)(de)新研究,增加(jia)有(you)(you)機硅(gui)材料在(zai)汽(qi)車零(ling)(ling)部件方(fang)面的(de)(de)(de)(de)用(yong)(yong)(yong)量,可以(yi)大幅度(du)提(ti)高(gao)汽(qi)車的(de)(de)(de)(de)安(an)全性能(neng),因(yin)此,汽(qi)車產量和單車用(yong)(yong)(yong)量水(shui)平的(de)(de)(de)(de)提(ti)高(gao)都將推動汽(qi)車工(gong)業對硅(gui)橡(xiang)膠(jiao)需求的(de)(de)(de)(de)增加(jia)。國(guo)家鼓勵(li)自主(zhu)品(pin)(pin)牌(pai)(pai)的(de)(de)(de)(de)汽(qi)車發(fa)展(zhan)(zhan),關鍵(jian)汽(qi)車零(ling)(ling)部件實現自主(zhu)化,《2012年(nian)(nian)度(du)黨政(zheng)機關公務用(yong)(yong)(yong)車選用(yong)(yong)(yong)車型(xing)目錄(征求意見(jian)稿)》為(wei)自主(zhu)品(pin)(pin)牌(pai)(pai)擴大在(zai)政(zheng)府(fu)采(cai)購(gou)的(de)(de)(de)(de)市場份額,為(wei)改變目前國(guo)內政(zheng)府(fu)采(cai)購(gou)以(yi)合資品(pin)(pin)牌(pai)(pai)產品(pin)(pin)為(wei)主(zhu)的(de)(de)(de)(de)局面提(ti)供了保障。促進(jin)自主(zhu)品(pin)(pin)牌(pai)(pai)發(fa)展(zhan)(zhan),國(guo)產汽(qi)車業的(de)(de)(de)(de)繁榮將為(wei)汽(qi)車膠(jiao)的(de)(de)(de)(de)應(ying)用(yong)(yong)(yong)提(ti)供有(you)(you)力保障。預測未來3年(nian)(nian),我國(guo)室溫(wen)硫化硅(gui)橡(xiang)膠(jiao)在(zai)汽(qi)車行(xing)業將以(yi)年(nian)(nian)均20%增長。
此外,硅(gui)(gui)(gui)橡膠(jiao)(jiao)(jiao)是重要的(de)(de)非石(shi)(shi)油(you)(you)(you)基(ji)(ji)合(he)成(cheng)橡膠(jiao)(jiao)(jiao),約占非石(shi)(shi)油(you)(you)(you)基(ji)(ji)合(he)成(cheng)橡膠(jiao)(jiao)(jiao)消費量(liang)的(de)(de)98%。但因為(wei)(wei)石(shi)(shi)油(you)(you)(you)價格的(de)(de)大(da)(da)(da)幅(fu)上(shang)漲(zhang),同時我國(guo)(guo)在硅(gui)(gui)(gui)橡膠(jiao)(jiao)(jiao)的(de)(de)關(guan)鍵原料有(you)機硅(gui)(gui)(gui)單(dan)體的(de)(de)生產(chan)技術(shu)方(fang)面取得突破,有(you)機硅(gui)(gui)(gui)單(dan)體的(de)(de)生產(chan)技術(shu)在2005年(nian)前被幾家跨國(guo)(guo)公司壟斷(duan),但目前我國(guo)(guo)已發(fa)展成(cheng)為(wei)(wei)全球(qiu)有(you)機硅(gui)(gui)(gui)單(dan)體第1大(da)(da)(da)國(guo)(guo),這2個(ge)方(fang)面原因使硅(gui)(gui)(gui)橡膠(jiao)(jiao)(jiao)的(de)(de)價格從2011年(nian)起(qi)開(kai)始低于石(shi)(shi)油(you)(you)(you)基(ji)(ji)合(he)成(cheng)橡膠(jiao)(jiao)(jiao),僅約為(wei)(wei)大(da)(da)(da)宗石(shi)(shi)油(you)(you)(you)基(ji)(ji)橡膠(jiao)(jiao)(jiao)的(de)(de)80%~90%,成(cheng)為(wei)(wei)廉價的(de)(de)合(he)成(cheng)橡膠(jiao)(jiao)(jiao),并開(kai)始大(da)(da)(da)規模替代石(shi)(shi)油(you)(you)(you)基(ji)(ji)合(he)成(cheng)橡膠(jiao)(jiao)(jiao)。這將(jiang)極大(da)(da)(da)拓展有(you)機硅(gui)(gui)(gui)產(chan)業(ye)的(de)(de)市場空間,同時將(jiang)帶(dai)動(dong)硅(gui)(gui)(gui)油(you)(you)(you)、硅(gui)(gui)(gui)烷偶聯(lian)劑和硅(gui)(gui)(gui)樹脂等其他有(you)機硅(gui)(gui)(gui)產(chan)品的(de)(de)消費。