
硅橡膠是指主鏈由硅(gui)(gui)和氧原子(zi)交替構(gou)成,硅(gui)(gui)原子(zi)上通常(chang)連有(you)兩個(ge)有(you)機基(ji)(ji)團的(de)(de)橡(xiang)(xiang)膠(jiao)(jiao)。普通的(de)(de)硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)主要由含甲基(ji)(ji)和少(shao)量乙烯基(ji)(ji)的(de)(de)硅(gui)(gui)氧鏈節組成。苯基(ji)(ji)的(de)(de)引入(ru)(ru)可(ke)(ke)(ke)提(ti)高(gao)(gao)硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)的(de)(de)耐(nai)高(gao)(gao)、低(di)溫(wen)性(xing)能(neng),三氟丙基(ji)(ji)及氰基(ji)(ji)的(de)(de)引入(ru)(ru)則可(ke)(ke)(ke)提(ti)高(gao)(gao)硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)的(de)(de)耐(nai)溫(wen)及耐(nai)油性(xing)能(neng)。硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)耐(nai)低(di)溫(wen)性(xing)能(neng)良好(hao)(hao),一般在(zai)-55℃下仍能(neng)工作。引入(ru)(ru)苯基(ji)(ji)后(hou),可(ke)(ke)(ke)達(da)-73℃。硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)的(de)(de)耐(nai)熱性(xing)能(neng)也很突(tu)出(chu),在(zai)180℃下可(ke)(ke)(ke)長(chang)期工作,稍(shao)高(gao)(gao)于(yu)200℃也能(neng)承受(shou)數周或更長(chang)時間仍有(you)彈(dan)性(xing),瞬時可(ke)(ke)(ke)耐(nai)300℃以(yi)上的(de)(de)高(gao)(gao)溫(wen)。硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)的(de)(de)透氣性(xing)好(hao)(hao),氧氣透過率(lv)在(zai)合(he)成聚合(he)物中是較高(gao)(gao)的(de)(de)。此(ci)外(wai),硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)還具有(you)生理(li)惰性(xing)、不會導致凝血(xue)的(de)(de)突(tu)出(chu)特(te)性(xing),因此(ci)在(zai)醫用領域應用廣(guang)泛。
主要品種
硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)分類的(de)方法很多,通(tong)常(chang)按(an)固化(hua)(hua)前的(de)形(xing)態分為固體(ti)硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)和(he)液體(ti)硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao);按(an)硫化(hua)(hua)溫度(du)分為室溫硫化(hua)(hua)硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao),高(gao)溫硫化(hua)(hua)硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao);按(an)所用單(dan)體(ti)的(de)不(bu)同(tong),可分為甲基(ji)(ji)乙(yi)烯(xi)基(ji)(ji)硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao),甲基(ji)(ji)苯基(ji)(ji)乙(yi)烯(xi)基(ji)(ji)硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)、氟(fu)硅(gui)(gui)(gui)(gui),腈硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)等;按(an)性能和(he)用途的(de)不(bu)同(tong)又(you)可分為通(tong)用型(xing)、超耐(nai)低溫型(xing)、超耐(nai)高(gao)溫型(xing)、高(gao)強力型(xing)、耐(nai)油型(xing)、醫用型(xing)等等。
發展史
硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)早(zao)期是由美(mei)國(guo)以三氯化(hua)鐵為催化(hua)劑合成的(de)。1945年,硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)產品問世(shi)。1948年,采用高比表(biao)面(mian)積的(de)氣相法白(bai)炭黑(hei)補強的(de)硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)研制(zhi)成功,使硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)的(de)性能躍升到實用階(jie)段,奠定了(le)現代(dai)硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)生(sheng)產技術(shu)的(de)基礎。從(cong)二甲基二氯硅(gui)(gui)烷合成開始生(sheng)產硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)的(de)國(guo)家有美(mei)國(guo)。俄(e)羅斯(si)、德國(guo)、日本、韓(han)國(guo)和中(zhong)國(guo)等。中(zhong)國(guo)硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)的(de)工業(ye)化(hua)研究始于(yu)1957年,多(duo)家研究所和企業(ye)陸續(xu)開發出各種硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)。到2003年底,中(zhong)國(guo)硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)生(sheng)產能力為135千(qian)噸,其中(zhong)高溫膠(jiao)(jiao)100千(qian)噸。
高溫硫化硅橡膠
高溫硫化(hua)(hua)(hua)硅橡膠(jiao)是(shi)指聚硅氧(yang)烷(wan)變成(cheng)彈性體的(de)過(guo)程是(shi)經過(guo)高溫(110-170℃)硫化(hua)(hua)(hua)成(cheng)型的(de)。它(ta)主(zhu)要(yao)以(yi)高分(fen)子量的(de)聚甲基(ji)乙烯基(ji)硅氧(yang)烷(wan)為生(sheng)膠(jiao),混入(ru)補強(qiang)填料、硫化(hua)(hua)(hua)劑(ji)(ji)等,在加(jia)熱加(jia)壓下硫化(hua)(hua)(hua)成(cheng)彈性體。硅橡膠(jiao)的(de)補強(qiang)主(zhu)要(yao)是(shi)各(ge)(ge)種(zhong)類型的(de)白(bai)炭黑,可使(shi)硫化(hua)(hua)(hua)膠(jiao)的(de)強(qiang)度增加(jia)數(shu)十倍。有(you)時為了降低(di)成(cheng)本或(huo)(huo)改善膠(jiao)料性能及賦予硫化(hua)(hua)(hua)膠(jiao)各(ge)(ge)種(zhong)特殊的(de)性能,也(ye)加(jia)入(ru)相應(ying)的(de)各(ge)(ge)種(zhong)添加(jia)劑(ji)(ji)。硫化(hua)(hua)(hua)劑(ji)(ji)是(shi)各(ge)(ge)種(zhong)有(you)機過(guo)氧(yang)化(hua)(hua)(hua)物或(huo)(huo)加(jia)成(cheng)反應(ying)催化(hua)(hua)(hua)劑(ji)(ji)。
加(jia)工成(cheng)型方(fang)法如圖所示。一次(ci)硫(liu)化(hua)(hua)的(de)(de)目的(de)(de)是進行高分子鏈的(de)(de)交聯(lian)反應;二次(ci)硫(liu)化(hua)(hua)的(de)(de)目的(de)(de)是進行補充交聯(lian)、驅除硫(liu)化(hua)(hua)劑(ji)分解產物和其(qi)他揮發(fa)性化(hua)(hua)合物以穩定硫(liu)化(hua)(hua)膠的(de)(de)各項性能(neng)。常用的(de)(de)設備有開放式煉膠機(ji)、捏合機(ji)及真空密(mi)煉機(ji)。
主要性能
(1)高溫(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)。硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)顯(xian)著的(de)特(te)征是(shi)高溫(wen)(wen)穩定(ding)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing),雖(sui)然常(chang)溫(wen)(wen)下(xia)硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)的(de)強度(du)僅是(shi)天然橡(xiang)(xiang)(xiang)膠(jiao)(jiao)或某(mou)些合(he)成橡(xiang)(xiang)(xiang)膠(jiao)(jiao)的(de)一半(ban),但在(zai)200℃以上的(de)高溫(wen)(wen)環境(jing)下(xia),硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)仍(reng)能(neng)保持(chi)一定(ding)的(de)柔(rou)韌性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)、回彈性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)和(he)表面硬度(du),且力學性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)無(wu)明(ming)(ming)顯(xian)變(bian)化(hua)。(2)低(di)溫(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)的(de)玻璃化(hua)溫(wen)(wen)度(du)一般(ban)為-70~-50℃,特(te)殊配(pei)方可達-100℃,表明(ming)(ming)其(qi)(qi)低(di)溫(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)優(you)異。這對(dui)航空(kong)、宇航工業(ye)的(de)意義重大(da)。(3)耐(nai)(nai)候性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)中Si-O-Si鍵對(dui)氧、臭氧及(ji)紫外線等(deng)(deng)(deng)十分穩定(ding),在(zai)不加任何添(tian)加劑(ji)的(de)情況下(xia),就具有(you)優(you)良(liang)的(de)耐(nai)(nai)候性(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)能(neng)。硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)具有(you)優(you)異的(de)絕緣性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng),耐(nai)(nai)電暈性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)和(he)耐(nai)(nai)電弧性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)也非常(chang)好。(5)物(wu)理(li)機(ji)械性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)。硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)常(chang)溫(wen)(wen)下(xia)的(de)物(wu)理(li)機(ji)械性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)比通(tong)用橡(xiang)(xiang)(xiang)膠(jiao)(jiao)差,但在(zai)150℃的(de)高溫(wen)(wen)和(he)-50℃的(de)低(di)溫(wen)(wen)下(xia),其(qi)(qi)物(wu)理(li)機(ji)械性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)優(you)于(yu)通(tong)用橡(xiang)(xiang)(xiang)膠(jiao)(jiao)。(6)耐(nai)(nai)油及(ji)化(hua)學試(shi)劑(ji)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)。普通(tong)硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)具有(you)中等(deng)(deng)(deng)的(de)耐(nai)(nai)油、耐(nai)(nai)溶劑(ji)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)。(7)氣(qi)(qi)體透過性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)。室溫(wen)(wen)下(xia)硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)對(dui)空(kong)氣(qi)(qi)、氮、氧、二氧化(hua)碳等(deng)(deng)(deng)氣(qi)(qi)體的(de)透氣(qi)(qi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)比天然橡(xiang)(xiang)(xiang)膠(jiao)(jiao)高出30-50倍(bei)。(8)生理(li)惰性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)。硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)無(wu)毒,無(wu)味,無(wu)嗅,與人體組織不粘連(lian),具有(you)抗凝血(xue)作用,對(dui)肌體組織的(de)反應性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)非常(chang)少。特(te)別(bie)適合(he)作為醫用材料。
硅橡膠的用量
據(ju)中國汽(qi)(qi)車(che)工(gong)(gong)業(ye)協會(hui)統計,2012年,汽(qi)(qi)車(che)產(chan)(chan)銷分別達(da)到(dao)1927.18萬(wan)輛和(he)1930.64萬(wan)輛,同比分別增長4.63%和(he)4.33%,汽(qi)(qi)車(che)工(gong)(gong)業(ye)硅(gui)(gui)橡(xiang)膠(jiao)的(de)(de)(de)(de)用(yong)量(liang)約達(da)2.0萬(wan)t。根據(ju)觀研(yan)天下(xia)的(de)(de)(de)(de)新研(yan)究,增加有(you)機(ji)硅(gui)(gui)材料(liao)在汽(qi)(qi)車(che)零部(bu)件方面(mian)的(de)(de)(de)(de)用(yong)量(liang),可(ke)以大(da)幅度(du)提(ti)高汽(qi)(qi)車(che)的(de)(de)(de)(de)安全性能,因此,汽(qi)(qi)車(che)產(chan)(chan)量(liang)和(he)單車(che)用(yong)量(liang)水平的(de)(de)(de)(de)提(ti)高都將(jiang)(jiang)推動汽(qi)(qi)車(che)工(gong)(gong)業(ye)對硅(gui)(gui)橡(xiang)膠(jiao)需求的(de)(de)(de)(de)增加。國家鼓勵自(zi)主(zhu)品(pin)牌的(de)(de)(de)(de)汽(qi)(qi)車(che)發(fa)展(zhan),關鍵汽(qi)(qi)車(che)零部(bu)件實現自(zi)主(zhu)化,《2012年度(du)黨政機(ji)關公務用(yong)車(che)選用(yong)車(che)型(xing)目錄(征求意見稿)》為(wei)(wei)自(zi)主(zhu)品(pin)牌擴大(da)在政府(fu)采購(gou)的(de)(de)(de)(de)市場份額,為(wei)(wei)改變目前國內政府(fu)采購(gou)以合資品(pin)牌產(chan)(chan)品(pin)為(wei)(wei)主(zhu)的(de)(de)(de)(de)局(ju)面(mian)提(ti)供了保(bao)障。促進自(zi)主(zhu)品(pin)牌發(fa)展(zhan),國產(chan)(chan)汽(qi)(qi)車(che)業(ye)的(de)(de)(de)(de)繁榮(rong)將(jiang)(jiang)為(wei)(wei)汽(qi)(qi)車(che)膠(jiao)的(de)(de)(de)(de)應(ying)用(yong)提(ti)供有(you)力保(bao)障。預測未(wei)來(lai)3年,我國室溫硫化硅(gui)(gui)橡(xiang)膠(jiao)在汽(qi)(qi)車(che)行業(ye)將(jiang)(jiang)以年均(jun)20%增長。
此外,硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)是(shi)重要的(de)非石(shi)(shi)油(you)基(ji)(ji)合(he)成(cheng)(cheng)(cheng)橡(xiang)(xiang)膠(jiao)(jiao),約占(zhan)非石(shi)(shi)油(you)基(ji)(ji)合(he)成(cheng)(cheng)(cheng)橡(xiang)(xiang)膠(jiao)(jiao)消費(fei)量(liang)的(de)98%。但(dan)因為(wei)(wei)(wei)石(shi)(shi)油(you)價格的(de)大(da)幅上漲,同時我(wo)(wo)國(guo)在硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)的(de)關鍵原料有(you)(you)(you)機硅(gui)(gui)單體(ti)(ti)的(de)生產(chan)(chan)(chan)技(ji)術(shu)方面取得突(tu)破(po),有(you)(you)(you)機硅(gui)(gui)單體(ti)(ti)的(de)生產(chan)(chan)(chan)技(ji)術(shu)在2005年前被幾(ji)家跨國(guo)公司壟斷,但(dan)目前我(wo)(wo)國(guo)已(yi)發展成(cheng)(cheng)(cheng)為(wei)(wei)(wei)全球有(you)(you)(you)機硅(gui)(gui)單體(ti)(ti)第1大(da)國(guo),這2個方面原因使硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)的(de)價格從(cong)2011年起(qi)開始(shi)低于石(shi)(shi)油(you)基(ji)(ji)合(he)成(cheng)(cheng)(cheng)橡(xiang)(xiang)膠(jiao)(jiao),僅約為(wei)(wei)(wei)大(da)宗石(shi)(shi)油(you)基(ji)(ji)橡(xiang)(xiang)膠(jiao)(jiao)的(de)80%~90%,成(cheng)(cheng)(cheng)為(wei)(wei)(wei)廉價的(de)合(he)成(cheng)(cheng)(cheng)橡(xiang)(xiang)膠(jiao)(jiao),并開始(shi)大(da)規模替代(dai)石(shi)(shi)油(you)基(ji)(ji)合(he)成(cheng)(cheng)(cheng)橡(xiang)(xiang)膠(jiao)(jiao)。這將極大(da)拓展有(you)(you)(you)機硅(gui)(gui)產(chan)(chan)(chan)業的(de)市場空間,同時將帶動硅(gui)(gui)油(you)、硅(gui)(gui)烷偶聯劑(ji)和硅(gui)(gui)樹脂等其他有(you)(you)(you)機硅(gui)(gui)產(chan)(chan)(chan)品的(de)消費(fei)。