硅橡膠是指主鏈由(you)硅(gui)(gui)(gui)(gui)(gui)和氧(yang)(yang)原(yuan)子交替構成,硅(gui)(gui)(gui)(gui)(gui)原(yuan)子上(shang)通(tong)常連有兩個有機基(ji)團的橡(xiang)膠。普通(tong)的硅(gui)(gui)(gui)(gui)(gui)橡(xiang)膠主要由(you)含(han)甲基(ji)和少量乙(yi)烯基(ji)的硅(gui)(gui)(gui)(gui)(gui)氧(yang)(yang)鏈節組成。苯(ben)基(ji)的引入可(ke)提高(gao)(gao)硅(gui)(gui)(gui)(gui)(gui)橡(xiang)膠的耐高(gao)(gao)、低(di)溫(wen)性(xing)能(neng)(neng),三氟(fu)丙基(ji)及(ji)氰基(ji)的引入則可(ke)提高(gao)(gao)硅(gui)(gui)(gui)(gui)(gui)橡(xiang)膠的耐溫(wen)及(ji)耐油性(xing)能(neng)(neng)。硅(gui)(gui)(gui)(gui)(gui)橡(xiang)膠耐低(di)溫(wen)性(xing)能(neng)(neng)良好,一般在(zai)-55℃下(xia)仍(reng)能(neng)(neng)工(gong)作。引入苯(ben)基(ji)后(hou),可(ke)達-73℃。硅(gui)(gui)(gui)(gui)(gui)橡(xiang)膠的耐熱性(xing)能(neng)(neng)也很突出,在(zai)180℃下(xia)可(ke)長期工(gong)作,稍高(gao)(gao)于(yu)200℃也能(neng)(neng)承受數周或更(geng)長時(shi)間(jian)仍(reng)有彈性(xing),瞬時(shi)可(ke)耐300℃以上(shang)的高(gao)(gao)溫(wen)。硅(gui)(gui)(gui)(gui)(gui)橡(xiang)膠的透氣性(xing)好,氧(yang)(yang)氣透過率在(zai)合(he)成聚合(he)物中是較高(gao)(gao)的。此外,硅(gui)(gui)(gui)(gui)(gui)橡(xiang)膠還具有生理(li)惰性(xing)、不會導致凝血的突出特性(xing),因此在(zai)醫(yi)用領(ling)域應用廣(guang)泛(fan)。
主要品種
硅(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)分(fen)(fen)類的方(fang)法很多,通常按(an)(an)固(gu)化前(qian)的形態分(fen)(fen)為(wei)固(gu)體硅(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)和液體硅(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao);按(an)(an)硫(liu)化溫度分(fen)(fen)為(wei)室溫硫(liu)化硅(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao),高溫硫(liu)化硅(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao);按(an)(an)所用(yong)單體的不同,可分(fen)(fen)為(wei)甲基(ji)乙(yi)烯(xi)基(ji)硅(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao),甲基(ji)苯基(ji)乙(yi)烯(xi)基(ji)硅(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)、氟硅(gui),腈硅(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)等;按(an)(an)性能(neng)和用(yong)途的不同又可分(fen)(fen)為(wei)通用(yong)型(xing)(xing)(xing)、超耐(nai)(nai)低溫型(xing)(xing)(xing)、超耐(nai)(nai)高溫型(xing)(xing)(xing)、高強力型(xing)(xing)(xing)、耐(nai)(nai)油型(xing)(xing)(xing)、醫用(yong)型(xing)(xing)(xing)等等。
發展史
硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)早期是由美(mei)(mei)國(guo)(guo)以三(san)氯化(hua)鐵為催化(hua)劑合(he)成(cheng)的(de)(de)(de)。1945年,硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)產品問(wen)世。1948年,采用高比表面積的(de)(de)(de)氣相(xiang)法白炭黑補(bu)強(qiang)的(de)(de)(de)硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)研(yan)制成(cheng)功,使硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)的(de)(de)(de)性能(neng)躍升(sheng)到實用階(jie)段(duan),奠(dian)定了(le)現(xian)代(dai)硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)生產技術的(de)(de)(de)基礎。從二甲(jia)基二氯硅(gui)(gui)烷合(he)成(cheng)開始(shi)生產硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)的(de)(de)(de)國(guo)(guo)家(jia)有美(mei)(mei)國(guo)(guo)。俄羅斯、德國(guo)(guo)、日本、韓國(guo)(guo)和中(zhong)國(guo)(guo)等(deng)。中(zhong)國(guo)(guo)硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)的(de)(de)(de)工業化(hua)研(yan)究(jiu)始(shi)于1957年,多家(jia)研(yan)究(jiu)所(suo)和企業陸續開發出各種硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)。到2003年底(di),中(zhong)國(guo)(guo)硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)生產能(neng)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(gao)溫(wen)(wen)硫化(hua)(hua)(hua)硅橡(xiang)膠(jiao)是指聚硅氧烷變成(cheng)(cheng)(cheng)彈性體的(de)過程是經過高(gao)溫(wen)(wen)(110-170℃)硫化(hua)(hua)(hua)成(cheng)(cheng)(cheng)型的(de)。它主要(yao)以高(gao)分子量的(de)聚甲基(ji)乙烯基(ji)硅氧烷為(wei)生膠(jiao),混入(ru)補強(qiang)填(tian)料、硫化(hua)(hua)(hua)劑等(deng),在加(jia)熱加(jia)壓下硫化(hua)(hua)(hua)成(cheng)(cheng)(cheng)彈性體。硅橡(xiang)膠(jiao)的(de)補強(qiang)主要(yao)是各種(zhong)類型的(de)白炭(tan)黑,可使硫化(hua)(hua)(hua)膠(jiao)的(de)強(qiang)度增加(jia)數十倍。有(you)時為(wei)了降(jiang)低成(cheng)(cheng)(cheng)本(ben)或(huo)改(gai)善(shan)膠(jiao)料性能及(ji)賦予硫化(hua)(hua)(hua)膠(jiao)各種(zhong)特殊(shu)的(de)性能,也加(jia)入(ru)相(xiang)應(ying)的(de)各種(zhong)添加(jia)劑。硫化(hua)(hua)(hua)劑是各種(zhong)有(you)機(ji)過氧化(hua)(hua)(hua)物或(huo)加(jia)成(cheng)(cheng)(cheng)反應(ying)催化(hua)(hua)(hua)劑。
加(jia)工成型方法如圖(tu)所示。一次硫(liu)(liu)化(hua)的(de)目(mu)的(de)是(shi)進行(xing)高(gao)分子鏈的(de)交(jiao)聯(lian)反應;二(er)次硫(liu)(liu)化(hua)的(de)目(mu)的(de)是(shi)進行(xing)補充交(jiao)聯(lian)、驅除硫(liu)(liu)化(hua)劑分解產物(wu)和其他揮發性(xing)化(hua)合(he)物(wu)以穩定硫(liu)(liu)化(hua)膠的(de)各(ge)項(xiang)性(xing)能(neng)。常用的(de)設(she)備有(you)開放式煉(lian)膠機(ji)(ji)、捏合(he)機(ji)(ji)及真空密煉(lian)機(ji)(ji)。
主要性能
(1)高(gao)(gao)溫(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)。硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)顯(xian)(xian)著的(de)(de)(de)(de)(de)特(te)(te)征是(shi)高(gao)(gao)溫(wen)穩定性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing),雖然(ran)常(chang)溫(wen)下(xia)硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)的(de)(de)(de)(de)(de)強度(du)僅是(shi)天(tian)然(ran)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)或某些合成橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)的(de)(de)(de)(de)(de)一半(ban),但在200℃以上的(de)(de)(de)(de)(de)高(gao)(gao)溫(wen)環(huan)境下(xia),硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)仍能(neng)(neng)(neng)保持一定的(de)(de)(de)(de)(de)柔韌性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)、回彈(dan)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)和表(biao)(biao)面硬度(du),且力(li)學性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)無明顯(xian)(xian)變化。(2)低(di)溫(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)的(de)(de)(de)(de)(de)玻璃(li)化溫(wen)度(du)一般(ban)為(wei)-70~-50℃,特(te)(te)殊配方可達-100℃,表(biao)(biao)明其(qi)低(di)溫(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)優(you)異。這(zhe)對航空、宇航工業的(de)(de)(de)(de)(de)意義重大。(3)耐(nai)候性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)中Si-O-Si鍵(jian)對氧(yang)、臭氧(yang)及紫外線等(deng)十分穩定,在不加任何添(tian)加劑(ji)的(de)(de)(de)(de)(de)情況(kuang)下(xia),就具(ju)有(you)(you)(you)優(you)良的(de)(de)(de)(de)(de)耐(nai)候性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)。(4)電氣(qi)(qi)(qi)(qi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)。硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)具(ju)有(you)(you)(you)優(you)異的(de)(de)(de)(de)(de)絕緣性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng),耐(nai)電暈性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)和耐(nai)電弧性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)也非常(chang)好。(5)物理(li)機械(xie)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)。硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)常(chang)溫(wen)下(xia)的(de)(de)(de)(de)(de)物理(li)機械(xie)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)比(bi)通用(yong)(yong)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)差(cha),但在150℃的(de)(de)(de)(de)(de)高(gao)(gao)溫(wen)和-50℃的(de)(de)(de)(de)(de)低(di)溫(wen)下(xia),其(qi)物理(li)機械(xie)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)優(you)于(yu)通用(yong)(yong)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)。(6)耐(nai)油及化學試劑(ji)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)。普通硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)具(ju)有(you)(you)(you)中等(deng)的(de)(de)(de)(de)(de)耐(nai)油、耐(nai)溶劑(ji)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)。(7)氣(qi)(qi)(qi)(qi)體(ti)透過(guo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)。室溫(wen)下(xia)硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)對空氣(qi)(qi)(qi)(qi)、氮、氧(yang)、二氧(yang)化碳等(deng)氣(qi)(qi)(qi)(qi)體(ti)的(de)(de)(de)(de)(de)透氣(qi)(qi)(qi)(qi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)比(bi)天(tian)然(ran)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)高(gao)(gao)出(chu)30-50倍(bei)。(8)生理(li)惰性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)。硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)無毒,無味,無嗅(xiu),與人體(ti)組(zu)織(zhi)(zhi)不粘連,具(ju)有(you)(you)(you)抗凝血作用(yong)(yong),對肌體(ti)組(zu)織(zhi)(zhi)的(de)(de)(de)(de)(de)反(fan)應性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)非常(chang)少。特(te)(te)別適(shi)合作為(wei)醫用(yong)(yong)材料。
硅橡膠的用量
據中(zhong)國(guo)汽(qi)車(che)(che)(che)工(gong)業協會統計,2012年(nian),汽(qi)車(che)(che)(che)產(chan)銷(xiao)分別達到1927.18萬輛和(he)(he)1930.64萬輛,同比分別增長4.63%和(he)(he)4.33%,汽(qi)車(che)(che)(che)工(gong)業硅(gui)橡(xiang)膠的(de)用(yong)(yong)量約達2.0萬t。根據觀(guan)研天下的(de)新研究,增加有機硅(gui)材料(liao)在汽(qi)車(che)(che)(che)零部件方面的(de)用(yong)(yong)量,可以(yi)大幅(fu)度提(ti)高(gao)汽(qi)車(che)(che)(che)的(de)安全性能,因此,汽(qi)車(che)(che)(che)產(chan)量和(he)(he)單(dan)車(che)(che)(che)用(yong)(yong)量水平的(de)提(ti)高(gao)都將(jiang)(jiang)推動(dong)汽(qi)車(che)(che)(che)工(gong)業對硅(gui)橡(xiang)膠需求的(de)增加。國(guo)家鼓勵自主(zhu)品(pin)(pin)牌(pai)的(de)汽(qi)車(che)(che)(che)發展,關(guan)鍵汽(qi)車(che)(che)(che)零部件實現(xian)自主(zhu)化,《2012年(nian)度黨政(zheng)機關(guan)公務用(yong)(yong)車(che)(che)(che)選用(yong)(yong)車(che)(che)(che)型(xing)目(mu)錄(征求意見(jian)稿(gao))》為(wei)自主(zhu)品(pin)(pin)牌(pai)擴大在政(zheng)府采購的(de)市(shi)場份額,為(wei)改(gai)變目(mu)前國(guo)內政(zheng)府采購以(yi)合資品(pin)(pin)牌(pai)產(chan)品(pin)(pin)為(wei)主(zhu)的(de)局面提(ti)供(gong)了保障。促(cu)進自主(zhu)品(pin)(pin)牌(pai)發展,國(guo)產(chan)汽(qi)車(che)(che)(che)業的(de)繁榮將(jiang)(jiang)為(wei)汽(qi)車(che)(che)(che)膠的(de)應用(yong)(yong)提(ti)供(gong)有力保障。預測未來3年(nian),我國(guo)室(shi)溫(wen)硫(liu)化硅(gui)橡(xiang)膠在汽(qi)車(che)(che)(che)行業將(jiang)(jiang)以(yi)年(nian)均20%增長。
此外,硅(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)是(shi)重要的(de)(de)(de)(de)非石(shi)(shi)(shi)油(you)基合(he)成橡(xiang)(xiang)(xiang)膠(jiao)(jiao),約占非石(shi)(shi)(shi)油(you)基合(he)成橡(xiang)(xiang)(xiang)膠(jiao)(jiao)消費量(liang)的(de)(de)(de)(de)98%。但因為石(shi)(shi)(shi)油(you)價格的(de)(de)(de)(de)大(da)幅上漲,同時我國(guo)在(zai)硅(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)的(de)(de)(de)(de)關(guan)鍵原料有(you)機(ji)硅(gui)單(dan)體的(de)(de)(de)(de)生(sheng)(sheng)產(chan)技術方面(mian)(mian)取得突破,有(you)機(ji)硅(gui)單(dan)體的(de)(de)(de)(de)生(sheng)(sheng)產(chan)技術在(zai)2005年(nian)前被幾家跨國(guo)公司壟(long)斷,但目前我國(guo)已發展成為全球有(you)機(ji)硅(gui)單(dan)體第1大(da)國(guo),這2個方面(mian)(mian)原因使(shi)硅(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)的(de)(de)(de)(de)價格從(cong)2011年(nian)起(qi)開(kai)始(shi)低于石(shi)(shi)(shi)油(you)基合(he)成橡(xiang)(xiang)(xiang)膠(jiao)(jiao),僅約為大(da)宗石(shi)(shi)(shi)油(you)基橡(xiang)(xiang)(xiang)膠(jiao)(jiao)的(de)(de)(de)(de)80%~90%,成為廉價的(de)(de)(de)(de)合(he)成橡(xiang)(xiang)(xiang)膠(jiao)(jiao),并開(kai)始(shi)大(da)規模替代(dai)石(shi)(shi)(shi)油(you)基合(he)成橡(xiang)(xiang)(xiang)膠(jiao)(jiao)。這將(jiang)極大(da)拓展有(you)機(ji)硅(gui)產(chan)業的(de)(de)(de)(de)市場空間,同時將(jiang)帶動硅(gui)油(you)、硅(gui)烷(wan)偶聯劑和硅(gui)樹脂等其他有(you)機(ji)硅(gui)產(chan)品的(de)(de)(de)(de)消費。