
硅橡膠是指主(zhu)鏈由硅(gui)(gui)和氧(yang)原子交(jiao)替(ti)構成,硅(gui)(gui)原子上通常連有兩(liang)個(ge)有機(ji)基團(tuan)的(de)(de)(de)(de)(de)橡(xiang)(xiang)(xiang)膠(jiao)。普通的(de)(de)(de)(de)(de)硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)主(zhu)要由含甲基和少量乙烯基的(de)(de)(de)(de)(de)硅(gui)(gui)氧(yang)鏈節組成。苯基的(de)(de)(de)(de)(de)引入(ru)可提高(gao)(gao)硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)的(de)(de)(de)(de)(de)耐(nai)(nai)高(gao)(gao)、低(di)(di)溫(wen)性(xing)能(neng),三氟丙(bing)基及氰基的(de)(de)(de)(de)(de)引入(ru)則可提高(gao)(gao)硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)的(de)(de)(de)(de)(de)耐(nai)(nai)溫(wen)及耐(nai)(nai)油性(xing)能(neng)。硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)耐(nai)(nai)低(di)(di)溫(wen)性(xing)能(neng)良(liang)好,一(yi)般在-55℃下(xia)仍能(neng)工(gong)作。引入(ru)苯基后,可達-73℃。硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)的(de)(de)(de)(de)(de)耐(nai)(nai)熱性(xing)能(neng)也很突出(chu),在180℃下(xia)可長期工(gong)作,稍高(gao)(gao)于200℃也能(neng)承(cheng)受數周(zhou)或更長時間仍有彈性(xing),瞬時可耐(nai)(nai)300℃以(yi)上的(de)(de)(de)(de)(de)高(gao)(gao)溫(wen)。硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)的(de)(de)(de)(de)(de)透(tou)氣性(xing)好,氧(yang)氣透(tou)過率在合成聚合物(wu)中是較高(gao)(gao)的(de)(de)(de)(de)(de)。此外,硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)還具有生理惰性(xing)、不(bu)會(hui)導致凝血的(de)(de)(de)(de)(de)突出(chu)特性(xing),因此在醫用領域應用廣泛。
主要品種
硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)分類的方法很(hen)多,通(tong)(tong)常按(an)(an)固(gu)化(hua)前(qian)的形態(tai)分為(wei)固(gu)體(ti)硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)和液(ye)體(ti)硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao);按(an)(an)硫(liu)(liu)化(hua)溫度分為(wei)室溫硫(liu)(liu)化(hua)硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao),高(gao)溫硫(liu)(liu)化(hua)硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao);按(an)(an)所(suo)用(yong)單體(ti)的不同,可分為(wei)甲基(ji)(ji)乙烯(xi)基(ji)(ji)硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao),甲基(ji)(ji)苯基(ji)(ji)乙烯(xi)基(ji)(ji)硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)、氟(fu)硅(gui)(gui)(gui)(gui),腈硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)等;按(an)(an)性能(neng)和用(yong)途的不同又可分為(wei)通(tong)(tong)用(yong)型(xing)(xing)(xing)、超耐低(di)溫型(xing)(xing)(xing)、超耐高(gao)溫型(xing)(xing)(xing)、高(gao)強(qiang)力型(xing)(xing)(xing)、耐油型(xing)(xing)(xing)、醫用(yong)型(xing)(xing)(xing)等等。
發展史
硅(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao)(jiao)早(zao)期是由(you)美國(guo)(guo)以三(san)氯(lv)(lv)化(hua)鐵為(wei)催化(hua)劑(ji)合(he)成的。1945年(nian),硅(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao)(jiao)產品問世。1948年(nian),采用高(gao)比(bi)表面積的氣相法(fa)白炭(tan)黑補(bu)強的硅(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao)(jiao)研(yan)制(zhi)成功,使硅(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao)(jiao)的性能躍升(sheng)到實用階(jie)段,奠定了現代硅(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao)(jiao)生產技術的基(ji)礎。從二甲基(ji)二氯(lv)(lv)硅(gui)(gui)烷合(he)成開(kai)始生產硅(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao)(jiao)的國(guo)(guo)家(jia)有(you)美國(guo)(guo)。俄(e)羅斯、德國(guo)(guo)、日本、韓國(guo)(guo)和(he)中(zhong)國(guo)(guo)等。中(zhong)國(guo)(guo)硅(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao)(jiao)的工業化(hua)研(yan)究始于1957年(nian),多家(jia)研(yan)究所和(he)企業陸續開(kai)發出各種硅(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao)(jiao)。到2003年(nian)底,中(zhong)國(guo)(guo)硅(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao)(jiao)生產能力(li)為(wei)135千噸,其中(zhong)高(gao)溫膠(jiao)(jiao)(jiao)(jiao)100千噸。
高溫硫化硅橡膠
高(gao)(gao)溫(wen)硫(liu)化(hua)(hua)(hua)(hua)硅(gui)(gui)橡(xiang)膠是(shi)指聚硅(gui)(gui)氧(yang)烷變成(cheng)彈性體的(de)(de)過(guo)程是(shi)經過(guo)高(gao)(gao)溫(wen)(110-170℃)硫(liu)化(hua)(hua)(hua)(hua)成(cheng)型的(de)(de)。它主要以高(gao)(gao)分子量的(de)(de)聚甲基乙烯(xi)基硅(gui)(gui)氧(yang)烷為生膠,混(hun)入補強(qiang)(qiang)(qiang)填(tian)料、硫(liu)化(hua)(hua)(hua)(hua)劑等(deng),在加(jia)(jia)(jia)熱加(jia)(jia)(jia)壓下硫(liu)化(hua)(hua)(hua)(hua)成(cheng)彈性體。硅(gui)(gui)橡(xiang)膠的(de)(de)補強(qiang)(qiang)(qiang)主要是(shi)各種(zhong)類型的(de)(de)白炭黑(hei),可(ke)使硫(liu)化(hua)(hua)(hua)(hua)膠的(de)(de)強(qiang)(qiang)(qiang)度(du)增加(jia)(jia)(jia)數十倍。有(you)時為了降(jiang)低成(cheng)本或改善膠料性能(neng)及賦予硫(liu)化(hua)(hua)(hua)(hua)膠各種(zhong)特殊的(de)(de)性能(neng),也加(jia)(jia)(jia)入相應的(de)(de)各種(zhong)添加(jia)(jia)(jia)劑。硫(liu)化(hua)(hua)(hua)(hua)劑是(shi)各種(zhong)有(you)機過(guo)氧(yang)化(hua)(hua)(hua)(hua)物或加(jia)(jia)(jia)成(cheng)反(fan)應催化(hua)(hua)(hua)(hua)劑。
加(jia)工成型方法如(ru)圖所示。一次(ci)硫化(hua)的(de)目(mu)的(de)是(shi)進行高分(fen)子鏈的(de)交聯反應;二次(ci)硫化(hua)的(de)目(mu)的(de)是(shi)進行補充交聯、驅除硫化(hua)劑分(fen)解(jie)產物和其他揮發性化(hua)合物以穩定硫化(hua)膠的(de)各(ge)項性能。常用的(de)設備有(you)開(kai)放式煉膠機(ji)、捏合機(ji)及真空密煉機(ji)。
主要性能
(1)高(gao)(gao)溫(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)。硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)顯著的(de)(de)(de)(de)(de)特征(zheng)是(shi)高(gao)(gao)溫(wen)穩(wen)定(ding)性(xing)(xing)(xing)(xing)(xing)(xing)(xing),雖然常溫(wen)下(xia)(xia)硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)的(de)(de)(de)(de)(de)強度(du)僅是(shi)天然橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)或某些合(he)成橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)的(de)(de)(de)(de)(de)一半,但(dan)在(zai)200℃以上的(de)(de)(de)(de)(de)高(gao)(gao)溫(wen)環境下(xia)(xia),硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)仍能(neng)(neng)(neng)保(bao)持一定(ding)的(de)(de)(de)(de)(de)柔韌(ren)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)、回彈性(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)能(neng)(neng)(neng)無明顯變化(hua)。(2)低溫(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)的(de)(de)(de)(de)(de)玻璃(li)化(hua)溫(wen)度(du)一般(ban)為-70~-50℃,特殊(shu)配方可達-100℃,表明其低溫(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)優(you)(you)異(yi)。這對(dui)航(hang)空、宇航(hang)工業(ye)的(de)(de)(de)(de)(de)意義重大(da)。(3)耐候性(xing)(xing)(xing)(xing)(xing)(xing)(xing)硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)中(zhong)Si-O-Si鍵對(dui)氧(yang)(yang)、臭氧(yang)(yang)及紫(zi)外(wai)線(xian)等十分穩(wen)定(ding),在(zai)不(bu)加(jia)任何(he)添加(jia)劑的(de)(de)(de)(de)(de)情況下(xia)(xia),就具(ju)(ju)有(you)(you)優(you)(you)良的(de)(de)(de)(de)(de)耐候性(xing)(xing)(xing)(xing)(xing)(xing)(xing)。(4)電(dian)氣(qi)(qi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)。硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)具(ju)(ju)有(you)(you)優(you)(you)異(yi)的(de)(de)(de)(de)(de)絕緣性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng),耐電(dian)暈(yun)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)和(he)(he)耐電(dian)弧性(xing)(xing)(xing)(xing)(xing)(xing)(xing)也非常好(hao)。(5)物理(li)機械性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)。硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)常溫(wen)下(xia)(xia)的(de)(de)(de)(de)(de)物理(li)機械性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)比通用(yong)(yong)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)差,但(dan)在(zai)150℃的(de)(de)(de)(de)(de)高(gao)(gao)溫(wen)和(he)(he)-50℃的(de)(de)(de)(de)(de)低溫(wen)下(xia)(xia),其物理(li)機械性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)優(you)(you)于(yu)通用(yong)(yong)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)。(6)耐油及化(hua)學試劑性(xing)(xing)(xing)(xing)(xing)(xing)(xing)。普通硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)具(ju)(ju)有(you)(you)中(zhong)等的(de)(de)(de)(de)(de)耐油、耐溶劑性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)。(7)氣(qi)(qi)體(ti)透過性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)。室溫(wen)下(xia)(xia)硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)對(dui)空氣(qi)(qi)、氮、氧(yang)(yang)、二氧(yang)(yang)化(hua)碳等氣(qi)(qi)體(ti)的(de)(de)(de)(de)(de)透氣(qi)(qi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)比天然橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)高(gao)(gao)出30-50倍。(8)生理(li)惰性(xing)(xing)(xing)(xing)(xing)(xing)(xing)。硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)無毒,無味,無嗅,與人(ren)體(ti)組織不(bu)粘連,具(ju)(ju)有(you)(you)抗凝血作用(yong)(yong),對(dui)肌體(ti)組織的(de)(de)(de)(de)(de)反應性(xing)(xing)(xing)(xing)(xing)(xing)(xing)非常少(shao)。特別適合(he)作為醫用(yong)(yong)材料。
硅橡膠的用量
據(ju)中國(guo)汽(qi)車(che)(che)工業協(xie)會統計,2012年(nian)(nian),汽(qi)車(che)(che)產銷分別達(da)到1927.18萬(wan)輛和1930.64萬(wan)輛,同比分別增長4.63%和4.33%,汽(qi)車(che)(che)工業硅(gui)(gui)橡(xiang)(xiang)膠(jiao)的用量(liang)約達(da)2.0萬(wan)t。根據(ju)觀研天(tian)下的新研究,增加有(you)機硅(gui)(gui)材料在(zai)汽(qi)車(che)(che)零(ling)部(bu)件方面的用量(liang),可以大幅(fu)度提(ti)(ti)高(gao)汽(qi)車(che)(che)的安全性能,因此,汽(qi)車(che)(che)產量(liang)和單車(che)(che)用量(liang)水平的提(ti)(ti)高(gao)都將(jiang)推動汽(qi)車(che)(che)工業對硅(gui)(gui)橡(xiang)(xiang)膠(jiao)需求的增加。國(guo)家鼓勵自主(zhu)品牌(pai)的汽(qi)車(che)(che)發展,關(guan)鍵汽(qi)車(che)(che)零(ling)部(bu)件實現自主(zhu)化(hua),《2012年(nian)(nian)度黨(dang)政(zheng)機關(guan)公務用車(che)(che)選用車(che)(che)型目錄(征(zheng)求意見稿)》為(wei)自主(zhu)品牌(pai)擴大在(zai)政(zheng)府采購(gou)的市場(chang)份額,為(wei)改變目前國(guo)內政(zheng)府采購(gou)以合資品牌(pai)產品為(wei)主(zhu)的局面提(ti)(ti)供了保(bao)障。促進自主(zhu)品牌(pai)發展,國(guo)產汽(qi)車(che)(che)業的繁榮將(jiang)為(wei)汽(qi)車(che)(che)膠(jiao)的應用提(ti)(ti)供有(you)力保(bao)障。預測未(wei)來3年(nian)(nian),我國(guo)室溫硫化(hua)硅(gui)(gui)橡(xiang)(xiang)膠(jiao)在(zai)汽(qi)車(che)(che)行業將(jiang)以年(nian)(nian)均20%增長。
此外,硅(gui)(gui)橡(xiang)(xiang)膠(jiao)是(shi)重要的(de)(de)非(fei)石(shi)油(you)(you)(you)(you)(you)基(ji)合(he)成(cheng)(cheng)(cheng)橡(xiang)(xiang)膠(jiao),約(yue)占非(fei)石(shi)油(you)(you)(you)(you)(you)基(ji)合(he)成(cheng)(cheng)(cheng)橡(xiang)(xiang)膠(jiao)消費(fei)量的(de)(de)98%。但因為石(shi)油(you)(you)(you)(you)(you)價格(ge)的(de)(de)大幅上漲,同(tong)時我國(guo)(guo)在(zai)硅(gui)(gui)橡(xiang)(xiang)膠(jiao)的(de)(de)關鍵原料(liao)有機(ji)硅(gui)(gui)單體的(de)(de)生(sheng)產(chan)(chan)技術方(fang)面(mian)取(qu)得(de)突破(po),有機(ji)硅(gui)(gui)單體的(de)(de)生(sheng)產(chan)(chan)技術在(zai)2005年前被幾家跨國(guo)(guo)公(gong)司壟斷,但目前我國(guo)(guo)已(yi)發展成(cheng)(cheng)(cheng)為全球有機(ji)硅(gui)(gui)單體第(di)1大國(guo)(guo),這2個方(fang)面(mian)原因使硅(gui)(gui)橡(xiang)(xiang)膠(jiao)的(de)(de)價格(ge)從2011年起開(kai)始低于石(shi)油(you)(you)(you)(you)(you)基(ji)合(he)成(cheng)(cheng)(cheng)橡(xiang)(xiang)膠(jiao),僅約(yue)為大宗石(shi)油(you)(you)(you)(you)(you)基(ji)橡(xiang)(xiang)膠(jiao)的(de)(de)80%~90%,成(cheng)(cheng)(cheng)為廉價的(de)(de)合(he)成(cheng)(cheng)(cheng)橡(xiang)(xiang)膠(jiao),并開(kai)始大規(gui)模替代石(shi)油(you)(you)(you)(you)(you)基(ji)合(he)成(cheng)(cheng)(cheng)橡(xiang)(xiang)膠(jiao)。這將(jiang)極大拓展有機(ji)硅(gui)(gui)產(chan)(chan)業的(de)(de)市場空間(jian),同(tong)時將(jiang)帶動硅(gui)(gui)油(you)(you)(you)(you)(you)、硅(gui)(gui)烷偶聯劑和硅(gui)(gui)樹脂等其他有機(ji)硅(gui)(gui)產(chan)(chan)品(pin)的(de)(de)消費(fei)。