硅橡膠是指主(zhu)鏈(lian)由硅(gui)(gui)(gui)和氧(yang)(yang)(yang)原子交替(ti)構成(cheng),硅(gui)(gui)(gui)原子上(shang)通常連有(you)兩個有(you)機(ji)基(ji)團(tuan)的橡(xiang)(xiang)膠。普通的硅(gui)(gui)(gui)橡(xiang)(xiang)膠主(zhu)要由含甲基(ji)和少量乙烯基(ji)的硅(gui)(gui)(gui)氧(yang)(yang)(yang)鏈(lian)節組成(cheng)。苯(ben)基(ji)的引入(ru)可(ke)提高(gao)硅(gui)(gui)(gui)橡(xiang)(xiang)膠的耐(nai)(nai)高(gao)、低溫性(xing)(xing)能,三氟丙基(ji)及氰基(ji)的引入(ru)則可(ke)提高(gao)硅(gui)(gui)(gui)橡(xiang)(xiang)膠的耐(nai)(nai)溫及耐(nai)(nai)油性(xing)(xing)能。硅(gui)(gui)(gui)橡(xiang)(xiang)膠耐(nai)(nai)低溫性(xing)(xing)能良好,一(yi)般(ban)在(zai)-55℃下(xia)仍能工(gong)作。引入(ru)苯(ben)基(ji)后,可(ke)達-73℃。硅(gui)(gui)(gui)橡(xiang)(xiang)膠的耐(nai)(nai)熱性(xing)(xing)能也很突(tu)出,在(zai)180℃下(xia)可(ke)長(chang)(chang)期工(gong)作,稍高(gao)于200℃也能承受數周或更(geng)長(chang)(chang)時間仍有(you)彈性(xing)(xing),瞬時可(ke)耐(nai)(nai)300℃以上(shang)的高(gao)溫。硅(gui)(gui)(gui)橡(xiang)(xiang)膠的透氣性(xing)(xing)好,氧(yang)(yang)(yang)氣透過率在(zai)合成(cheng)聚(ju)合物(wu)中是較高(gao)的。此外,硅(gui)(gui)(gui)橡(xiang)(xiang)膠還具(ju)有(you)生(sheng)理(li)惰性(xing)(xing)、不會導致凝血的突(tu)出特性(xing)(xing),因此在(zai)醫用領(ling)域應用廣泛(fan)。
主要品種
硅橡(xiang)(xiang)膠分類(lei)的(de)方法很(hen)多,通常按(an)(an)固(gu)(gu)化(hua)(hua)前的(de)形態分為固(gu)(gu)體(ti)硅橡(xiang)(xiang)膠和液體(ti)硅橡(xiang)(xiang)膠;按(an)(an)硫化(hua)(hua)溫(wen)度分為室溫(wen)硫化(hua)(hua)硅橡(xiang)(xiang)膠,高溫(wen)硫化(hua)(hua)硅橡(xiang)(xiang)膠;按(an)(an)所用(yong)(yong)單體(ti)的(de)不同(tong),可分為甲基乙(yi)烯(xi)基硅橡(xiang)(xiang)膠,甲基苯基乙(yi)烯(xi)基硅橡(xiang)(xiang)膠、氟硅,腈硅橡(xiang)(xiang)膠等(deng);按(an)(an)性能和用(yong)(yong)途的(de)不同(tong)又可分為通用(yong)(yong)型(xing)、超耐低溫(wen)型(xing)、超耐高溫(wen)型(xing)、高強力(li)型(xing)、耐油型(xing)、醫用(yong)(yong)型(xing)等(deng)等(deng)。
發展史
硅(gui)(gui)(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)早期(qi)是由美(mei)國(guo)(guo)以三氯化鐵為(wei)(wei)催化劑合(he)成(cheng)的(de)。1945年(nian),硅(gui)(gui)(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)產品(pin)問世(shi)。1948年(nian),采用高比表面積的(de)氣相法(fa)白炭黑補強的(de)硅(gui)(gui)(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)研制成(cheng)功,使硅(gui)(gui)(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)的(de)性能躍升(sheng)到實用階(jie)段,奠定了現代硅(gui)(gui)(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)生產技術的(de)基礎。從(cong)二(er)甲(jia)基二(er)氯硅(gui)(gui)(gui)(gui)(gui)烷合(he)成(cheng)開始(shi)生產硅(gui)(gui)(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)的(de)國(guo)(guo)家有美(mei)國(guo)(guo)。俄羅斯(si)、德(de)國(guo)(guo)、日本、韓國(guo)(guo)和中(zhong)(zhong)國(guo)(guo)等。中(zhong)(zhong)國(guo)(guo)硅(gui)(gui)(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)的(de)工業化研究(jiu)始(shi)于1957年(nian),多家研究(jiu)所和企業陸續開發出(chu)各(ge)種硅(gui)(gui)(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)。到2003年(nian)底,中(zhong)(zhong)國(guo)(guo)硅(gui)(gui)(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)生產能力為(wei)(wei)135千噸,其中(zhong)(zhong)高溫膠(jiao)(jiao)(jiao)(jiao)(jiao)100千噸。
高溫硫化硅橡膠
高(gao)溫硫(liu)(liu)化(hua)(hua)硅(gui)橡膠(jiao)(jiao)是(shi)指聚(ju)硅(gui)氧(yang)(yang)烷變成(cheng)(cheng)彈性(xing)體的(de)過程是(shi)經過高(gao)溫(110-170℃)硫(liu)(liu)化(hua)(hua)成(cheng)(cheng)型的(de)。它主(zhu)要(yao)以高(gao)分(fen)子量的(de)聚(ju)甲基乙烯基硅(gui)氧(yang)(yang)烷為(wei)生膠(jiao)(jiao),混入(ru)補強填料(liao)、硫(liu)(liu)化(hua)(hua)劑(ji)等,在加(jia)熱(re)加(jia)壓(ya)下硫(liu)(liu)化(hua)(hua)成(cheng)(cheng)彈性(xing)體。硅(gui)橡膠(jiao)(jiao)的(de)補強主(zhu)要(yao)是(shi)各種(zhong)類型的(de)白炭(tan)黑,可使硫(liu)(liu)化(hua)(hua)膠(jiao)(jiao)的(de)強度增加(jia)數十(shi)倍。有(you)(you)時為(wei)了(le)降低(di)成(cheng)(cheng)本或改(gai)善膠(jiao)(jiao)料(liao)性(xing)能(neng)及賦予硫(liu)(liu)化(hua)(hua)膠(jiao)(jiao)各種(zhong)特(te)殊的(de)性(xing)能(neng),也加(jia)入(ru)相(xiang)應的(de)各種(zhong)添(tian)加(jia)劑(ji)。硫(liu)(liu)化(hua)(hua)劑(ji)是(shi)各種(zhong)有(you)(you)機過氧(yang)(yang)化(hua)(hua)物或加(jia)成(cheng)(cheng)反應催化(hua)(hua)劑(ji)。
加工成型方法如圖所示。一次硫化(hua)(hua)的(de)(de)目(mu)的(de)(de)是進行(xing)高(gao)分子鏈的(de)(de)交聯(lian)反應;二次硫化(hua)(hua)的(de)(de)目(mu)的(de)(de)是進行(xing)補(bu)充(chong)交聯(lian)、驅除(chu)硫化(hua)(hua)劑分解(jie)產物和(he)其他揮(hui)發性(xing)(xing)化(hua)(hua)合(he)(he)物以穩定(ding)硫化(hua)(hua)膠的(de)(de)各項性(xing)(xing)能(neng)。常(chang)用的(de)(de)設(she)備有開放式煉(lian)膠機(ji)、捏(nie)合(he)(he)機(ji)及真(zhen)空密煉(lian)機(ji)。
主要性能
(1)高溫(wen)(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)。硅(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)顯(xian)著(zhu)的(de)(de)特(te)征(zheng)是高溫(wen)(wen)(wen)穩定性(xing)(xing)(xing)(xing)(xing)(xing),雖(sui)然常溫(wen)(wen)(wen)下(xia)(xia)硅(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)的(de)(de)強度僅是天(tian)然橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)或某些(xie)合成橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)的(de)(de)一半,但(dan)在(zai)200℃以上的(de)(de)高溫(wen)(wen)(wen)環境下(xia)(xia),硅(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)仍能(neng)(neng)(neng)保(bao)持(chi)一定的(de)(de)柔韌性(xing)(xing)(xing)(xing)(xing)(xing)、回彈(dan)性(xing)(xing)(xing)(xing)(xing)(xing)和表面硬度,且力(li)學(xue)性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)無明(ming)顯(xian)變化。(2)低溫(wen)(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)硅(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)的(de)(de)玻璃化溫(wen)(wen)(wen)度一般為(wei)-70~-50℃,特(te)殊(shu)配方可達-100℃,表明(ming)其低溫(wen)(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)優(you)(you)異(yi)。這對航空(kong)、宇航工業的(de)(de)意義重大(da)。(3)耐(nai)(nai)(nai)(nai)候性(xing)(xing)(xing)(xing)(xing)(xing)硅(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)中Si-O-Si鍵(jian)對氧、臭氧及紫(zi)外線等(deng)(deng)十分(fen)穩定,在(zai)不(bu)加任何添加劑的(de)(de)情況下(xia)(xia),就具有(you)優(you)(you)良的(de)(de)耐(nai)(nai)(nai)(nai)候性(xing)(xing)(xing)(xing)(xing)(xing)。(4)電氣(qi)(qi)性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)。硅(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)具有(you)優(you)(you)異(yi)的(de)(de)絕緣性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng),耐(nai)(nai)(nai)(nai)電暈性(xing)(xing)(xing)(xing)(xing)(xing)和耐(nai)(nai)(nai)(nai)電弧性(xing)(xing)(xing)(xing)(xing)(xing)也(ye)非常好。(5)物理機(ji)(ji)械性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)。硅(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)常溫(wen)(wen)(wen)下(xia)(xia)的(de)(de)物理機(ji)(ji)械性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)比(bi)通(tong)用(yong)(yong)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)差(cha),但(dan)在(zai)150℃的(de)(de)高溫(wen)(wen)(wen)和-50℃的(de)(de)低溫(wen)(wen)(wen)下(xia)(xia),其物理機(ji)(ji)械性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)優(you)(you)于通(tong)用(yong)(yong)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)。(6)耐(nai)(nai)(nai)(nai)油(you)及化學(xue)試劑性(xing)(xing)(xing)(xing)(xing)(xing)。普(pu)通(tong)硅(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)具有(you)中等(deng)(deng)的(de)(de)耐(nai)(nai)(nai)(nai)油(you)、耐(nai)(nai)(nai)(nai)溶劑性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)。(7)氣(qi)(qi)體透過性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)。室溫(wen)(wen)(wen)下(xia)(xia)硅(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)對空(kong)氣(qi)(qi)、氮、氧、二(er)氧化碳等(deng)(deng)氣(qi)(qi)體的(de)(de)透氣(qi)(qi)性(xing)(xing)(xing)(xing)(xing)(xing)比(bi)天(tian)然橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)高出30-50倍。(8)生理惰性(xing)(xing)(xing)(xing)(xing)(xing)。硅(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)無毒,無味,無嗅,與人(ren)體組織不(bu)粘連,具有(you)抗凝血作(zuo)用(yong)(yong),對肌體組織的(de)(de)反(fan)應(ying)性(xing)(xing)(xing)(xing)(xing)(xing)非常少。特(te)別(bie)適合作(zuo)為(wei)醫用(yong)(yong)材料(liao)。
硅橡膠的用量
據中國(guo)汽(qi)(qi)(qi)車(che)(che)工(gong)業協會(hui)統計,2012年,汽(qi)(qi)(qi)車(che)(che)產銷分別達到1927.18萬(wan)輛(liang)和(he)1930.64萬(wan)輛(liang),同比分別增(zeng)(zeng)長4.63%和(he)4.33%,汽(qi)(qi)(qi)車(che)(che)工(gong)業硅(gui)(gui)橡膠的(de)(de)(de)(de)(de)用(yong)(yong)量(liang)(liang)(liang)約(yue)達2.0萬(wan)t。根據觀研(yan)天下(xia)的(de)(de)(de)(de)(de)新研(yan)究(jiu),增(zeng)(zeng)加(jia)有機硅(gui)(gui)材(cai)料在汽(qi)(qi)(qi)車(che)(che)零(ling)(ling)部件方(fang)面(mian)的(de)(de)(de)(de)(de)用(yong)(yong)量(liang)(liang)(liang),可以大幅度提高(gao)汽(qi)(qi)(qi)車(che)(che)的(de)(de)(de)(de)(de)安全(quan)性能,因此(ci),汽(qi)(qi)(qi)車(che)(che)產量(liang)(liang)(liang)和(he)單車(che)(che)用(yong)(yong)量(liang)(liang)(liang)水平的(de)(de)(de)(de)(de)提高(gao)都(dou)將推動(dong)汽(qi)(qi)(qi)車(che)(che)工(gong)業對(dui)硅(gui)(gui)橡膠需求的(de)(de)(de)(de)(de)增(zeng)(zeng)加(jia)。國(guo)家鼓勵自主(zhu)(zhu)品(pin)牌的(de)(de)(de)(de)(de)汽(qi)(qi)(qi)車(che)(che)發展,關(guan)(guan)鍵汽(qi)(qi)(qi)車(che)(che)零(ling)(ling)部件實現(xian)自主(zhu)(zhu)化,《2012年度黨政(zheng)機關(guan)(guan)公(gong)務用(yong)(yong)車(che)(che)選用(yong)(yong)車(che)(che)型(xing)目(mu)錄(lu)(征(zheng)求意見稿(gao))》為(wei)自主(zhu)(zhu)品(pin)牌擴大在政(zheng)府(fu)采購的(de)(de)(de)(de)(de)市場份額,為(wei)改變(bian)目(mu)前國(guo)內(nei)政(zheng)府(fu)采購以合資品(pin)牌產品(pin)為(wei)主(zhu)(zhu)的(de)(de)(de)(de)(de)局(ju)面(mian)提供了保障。促進自主(zhu)(zhu)品(pin)牌發展,國(guo)產汽(qi)(qi)(qi)車(che)(che)業的(de)(de)(de)(de)(de)繁榮(rong)將為(wei)汽(qi)(qi)(qi)車(che)(che)膠的(de)(de)(de)(de)(de)應用(yong)(yong)提供有力保障。預(yu)測未(wei)來3年,我國(guo)室溫硫(liu)化硅(gui)(gui)橡膠在汽(qi)(qi)(qi)車(che)(che)行業將以年均20%增(zeng)(zeng)長。
此(ci)外,硅(gui)(gui)(gui)橡膠(jiao)(jiao)(jiao)是重(zhong)要的(de)非(fei)石(shi)(shi)(shi)油(you)(you)基(ji)(ji)合(he)(he)成(cheng)橡膠(jiao)(jiao)(jiao),約占(zhan)非(fei)石(shi)(shi)(shi)油(you)(you)基(ji)(ji)合(he)(he)成(cheng)橡膠(jiao)(jiao)(jiao)消(xiao)費量的(de)98%。但因(yin)為(wei)石(shi)(shi)(shi)油(you)(you)價(jia)格的(de)大(da)(da)幅(fu)上漲,同時(shi)我國在(zai)硅(gui)(gui)(gui)橡膠(jiao)(jiao)(jiao)的(de)關(guan)鍵原料(liao)有(you)機(ji)硅(gui)(gui)(gui)單體的(de)生產技術(shu)(shu)方面取得突破,有(you)機(ji)硅(gui)(gui)(gui)單體的(de)生產技術(shu)(shu)在(zai)2005年(nian)前被幾家跨國公(gong)司(si)壟斷,但目(mu)前我國已(yi)發展成(cheng)為(wei)全球(qiu)有(you)機(ji)硅(gui)(gui)(gui)單體第1大(da)(da)國,這2個(ge)方面原因(yin)使硅(gui)(gui)(gui)橡膠(jiao)(jiao)(jiao)的(de)價(jia)格從2011年(nian)起開始低于石(shi)(shi)(shi)油(you)(you)基(ji)(ji)合(he)(he)成(cheng)橡膠(jiao)(jiao)(jiao),僅約為(wei)大(da)(da)宗(zong)石(shi)(shi)(shi)油(you)(you)基(ji)(ji)橡膠(jiao)(jiao)(jiao)的(de)80%~90%,成(cheng)為(wei)廉價(jia)的(de)合(he)(he)成(cheng)橡膠(jiao)(jiao)(jiao),并開始大(da)(da)規模替代(dai)石(shi)(shi)(shi)油(you)(you)基(ji)(ji)合(he)(he)成(cheng)橡膠(jiao)(jiao)(jiao)。這將極大(da)(da)拓展有(you)機(ji)硅(gui)(gui)(gui)產業的(de)市場空間,同時(shi)將帶動硅(gui)(gui)(gui)油(you)(you)、硅(gui)(gui)(gui)烷偶聯劑(ji)和硅(gui)(gui)(gui)樹脂等其他有(you)機(ji)硅(gui)(gui)(gui)產品的(de)消(xiao)費。