
硅橡膠是指主鏈(lian)由硅(gui)(gui)和(he)氧(yang)原子(zi)交(jiao)替構成(cheng),硅(gui)(gui)原子(zi)上(shang)通常(chang)連(lian)有(you)(you)兩個(ge)有(you)(you)機基(ji)(ji)(ji)團的(de)橡(xiang)(xiang)(xiang)(xiang)膠。普通的(de)硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠主要由含甲(jia)基(ji)(ji)(ji)和(he)少量乙(yi)烯基(ji)(ji)(ji)的(de)硅(gui)(gui)氧(yang)鏈(lian)節組(zu)成(cheng)。苯基(ji)(ji)(ji)的(de)引(yin)入(ru)(ru)可(ke)提(ti)高硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠的(de)耐高、低溫(wen)性(xing)能(neng),三(san)氟丙基(ji)(ji)(ji)及(ji)氰基(ji)(ji)(ji)的(de)引(yin)入(ru)(ru)則(ze)可(ke)提(ti)高硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠的(de)耐溫(wen)及(ji)耐油性(xing)能(neng)。硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠耐低溫(wen)性(xing)能(neng)良好,一般在(zai)-55℃下仍(reng)能(neng)工作。引(yin)入(ru)(ru)苯基(ji)(ji)(ji)后,可(ke)達-73℃。硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠的(de)耐熱性(xing)能(neng)也(ye)很突(tu)出(chu),在(zai)180℃下可(ke)長(chang)期(qi)工作,稍高于200℃也(ye)能(neng)承受(shou)數(shu)周或更長(chang)時間(jian)仍(reng)有(you)(you)彈性(xing),瞬時可(ke)耐300℃以上(shang)的(de)高溫(wen)。硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠的(de)透氣性(xing)好,氧(yang)氣透過率在(zai)合成(cheng)聚(ju)合物中(zhong)是較高的(de)。此外,硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠還具有(you)(you)生理惰性(xing)、不會(hui)導致凝血的(de)突(tu)出(chu)特性(xing),因此在(zai)醫用(yong)領域應(ying)用(yong)廣(guang)泛。
主要品種
硅(gui)(gui)(gui)橡(xiang)膠分類(lei)的方法很多,通常按(an)固化前的形態分為(wei)固體(ti)(ti)硅(gui)(gui)(gui)橡(xiang)膠和液體(ti)(ti)硅(gui)(gui)(gui)橡(xiang)膠;按(an)硫化溫度分為(wei)室(shi)溫硫化硅(gui)(gui)(gui)橡(xiang)膠,高(gao)溫硫化硅(gui)(gui)(gui)橡(xiang)膠;按(an)所用(yong)單體(ti)(ti)的不同,可(ke)(ke)分為(wei)甲基(ji)(ji)乙烯基(ji)(ji)硅(gui)(gui)(gui)橡(xiang)膠,甲基(ji)(ji)苯基(ji)(ji)乙烯基(ji)(ji)硅(gui)(gui)(gui)橡(xiang)膠、氟(fu)硅(gui)(gui)(gui),腈硅(gui)(gui)(gui)橡(xiang)膠等;按(an)性能(neng)和用(yong)途(tu)的不同又(you)可(ke)(ke)分為(wei)通用(yong)型(xing)、超耐低(di)溫型(xing)、超耐高(gao)溫型(xing)、高(gao)強力(li)型(xing)、耐油型(xing)、醫用(yong)型(xing)等等。
發展史
硅橡(xiang)膠早期(qi)是由美(mei)國(guo)以三(san)氯化鐵為催化劑合(he)成(cheng)的(de)(de)(de)(de)。1945年,硅橡(xiang)膠產品(pin)問世。1948年,采用(yong)高(gao)比表(biao)面積的(de)(de)(de)(de)氣相法白炭(tan)黑補強的(de)(de)(de)(de)硅橡(xiang)膠研制成(cheng)功,使硅橡(xiang)膠的(de)(de)(de)(de)性能躍升到實用(yong)階段,奠定了現代硅橡(xiang)膠生(sheng)(sheng)產技術的(de)(de)(de)(de)基礎。從(cong)二甲基二氯硅烷合(he)成(cheng)開始生(sheng)(sheng)產硅橡(xiang)膠的(de)(de)(de)(de)國(guo)家有(you)美(mei)國(guo)。俄羅斯、德國(guo)、日本、韓國(guo)和(he)中(zhong)國(guo)等。中(zhong)國(guo)硅橡(xiang)膠的(de)(de)(de)(de)工業(ye)化研究(jiu)始于1957年,多家研究(jiu)所和(he)企業(ye)陸(lu)續開發出(chu)各(ge)種硅橡(xiang)膠。到2003年底,中(zhong)國(guo)硅橡(xiang)膠生(sheng)(sheng)產能力為135千(qian)噸,其(qi)中(zhong)高(gao)溫膠100千(qian)噸。
高溫硫化硅橡膠
高溫硫(liu)(liu)化(hua)硅橡(xiang)膠是(shi)指(zhi)聚硅氧(yang)(yang)烷變成(cheng)(cheng)彈性(xing)體的過(guo)程是(shi)經(jing)過(guo)高溫(110-170℃)硫(liu)(liu)化(hua)成(cheng)(cheng)型(xing)的。它主(zhu)要(yao)以高分(fen)子量的聚甲基(ji)乙(yi)烯基(ji)硅氧(yang)(yang)烷為生膠,混入補(bu)強(qiang)(qiang)填(tian)料(liao)、硫(liu)(liu)化(hua)劑(ji)等,在加(jia)(jia)熱加(jia)(jia)壓下硫(liu)(liu)化(hua)成(cheng)(cheng)彈性(xing)體。硅橡(xiang)膠的補(bu)強(qiang)(qiang)主(zhu)要(yao)是(shi)各(ge)種(zhong)(zhong)類型(xing)的白炭黑,可(ke)使硫(liu)(liu)化(hua)膠的強(qiang)(qiang)度增(zeng)加(jia)(jia)數十(shi)倍。有時(shi)為了(le)降低(di)成(cheng)(cheng)本(ben)或(huo)改善膠料(liao)性(xing)能及賦予(yu)硫(liu)(liu)化(hua)膠各(ge)種(zhong)(zhong)特殊的性(xing)能,也加(jia)(jia)入相應的各(ge)種(zhong)(zhong)添加(jia)(jia)劑(ji)。硫(liu)(liu)化(hua)劑(ji)是(shi)各(ge)種(zhong)(zhong)有機過(guo)氧(yang)(yang)化(hua)物或(huo)加(jia)(jia)成(cheng)(cheng)反應催化(hua)劑(ji)。
加工成(cheng)型方法(fa)如(ru)圖所示。一次硫(liu)化(hua)(hua)的(de)(de)(de)目的(de)(de)(de)是進行高(gao)分子鏈的(de)(de)(de)交聯反(fan)應;二次硫(liu)化(hua)(hua)的(de)(de)(de)目的(de)(de)(de)是進行補充交聯、驅除硫(liu)化(hua)(hua)劑分解產物和其他揮發(fa)性化(hua)(hua)合物以穩定硫(liu)化(hua)(hua)膠(jiao)的(de)(de)(de)各(ge)項性能(neng)。常(chang)用的(de)(de)(de)設備(bei)有開(kai)放式煉(lian)膠(jiao)機(ji)、捏合機(ji)及真空(kong)密煉(lian)機(ji)。
主要性能
(1)高溫(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)。硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)顯(xian)(xian)著的(de)(de)特(te)征是高溫(wen)(wen)穩定性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing),雖然(ran)常(chang)溫(wen)(wen)下(xia)(xia)硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)的(de)(de)強(qiang)度(du)僅是天然(ran)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)或某些合(he)成橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)的(de)(de)一半,但在200℃以上的(de)(de)高溫(wen)(wen)環境下(xia)(xia),硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)仍能(neng)(neng)保持(chi)一定的(de)(de)柔韌(ren)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)、回彈性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)和表面硬度(du),且(qie)力學(xue)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)無(wu)明顯(xian)(xian)變化(hua)。(2)低(di)溫(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)的(de)(de)玻璃化(hua)溫(wen)(wen)度(du)一般(ban)為(wei)-70~-50℃,特(te)殊配方(fang)可達-100℃,表明其低(di)溫(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)優(you)異。這對航空、宇航工業的(de)(de)意義(yi)重大。(3)耐(nai)候性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)中Si-O-Si鍵對氧、臭氧及(ji)紫外線等(deng)十分穩定,在不加任何添加劑(ji)(ji)的(de)(de)情況下(xia)(xia),就具(ju)(ju)(ju)有優(you)良的(de)(de)耐(nai)候性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)。(4)電(dian)氣性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)。硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)具(ju)(ju)(ju)有優(you)異的(de)(de)絕緣性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng),耐(nai)電(dian)暈性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)和耐(nai)電(dian)弧性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)也(ye)非常(chang)好。(5)物(wu)(wu)理(li)機械性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)。硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)常(chang)溫(wen)(wen)下(xia)(xia)的(de)(de)物(wu)(wu)理(li)機械性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)比(bi)(bi)通(tong)用(yong)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)差(cha),但在150℃的(de)(de)高溫(wen)(wen)和-50℃的(de)(de)低(di)溫(wen)(wen)下(xia)(xia),其物(wu)(wu)理(li)機械性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)優(you)于(yu)通(tong)用(yong)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)。(6)耐(nai)油及(ji)化(hua)學(xue)試劑(ji)(ji)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)。普通(tong)硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)具(ju)(ju)(ju)有中等(deng)的(de)(de)耐(nai)油、耐(nai)溶(rong)劑(ji)(ji)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)。(7)氣體(ti)(ti)透(tou)(tou)過性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)。室溫(wen)(wen)下(xia)(xia)硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)對空氣、氮、氧、二氧化(hua)碳等(deng)氣體(ti)(ti)的(de)(de)透(tou)(tou)氣性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)比(bi)(bi)天然(ran)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)高出(chu)30-50倍。(8)生(sheng)理(li)惰性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)。硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)無(wu)毒(du),無(wu)味,無(wu)嗅,與人(ren)體(ti)(ti)組織(zhi)不粘(zhan)連,具(ju)(ju)(ju)有抗凝血作用(yong),對肌體(ti)(ti)組織(zhi)的(de)(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(wei)醫用(yong)材料。
硅橡膠的用量
據中國汽(qi)車(che)(che)(che)工(gong)業(ye)協會統計,2012年,汽(qi)車(che)(che)(che)產(chan)銷分別達到1927.18萬(wan)輛和1930.64萬(wan)輛,同比分別增(zeng)長4.63%和4.33%,汽(qi)車(che)(che)(che)工(gong)業(ye)硅(gui)橡膠(jiao)的(de)用(yong)(yong)量(liang)約達2.0萬(wan)t。根據觀研(yan)天下的(de)新研(yan)究,增(zeng)加(jia)有(you)機硅(gui)材料(liao)在汽(qi)車(che)(che)(che)零(ling)部件方面的(de)用(yong)(yong)量(liang),可以(yi)(yi)大幅度提(ti)(ti)(ti)高(gao)汽(qi)車(che)(che)(che)的(de)安全性能(neng),因此,汽(qi)車(che)(che)(che)產(chan)量(liang)和單車(che)(che)(che)用(yong)(yong)量(liang)水平(ping)的(de)提(ti)(ti)(ti)高(gao)都(dou)將(jiang)推動汽(qi)車(che)(che)(che)工(gong)業(ye)對(dui)硅(gui)橡膠(jiao)需求(qiu)的(de)增(zeng)加(jia)。國家鼓勵自主品牌(pai)的(de)汽(qi)車(che)(che)(che)發展,關鍵汽(qi)車(che)(che)(che)零(ling)部件實(shi)現自主化,《2012年度黨政機關公務用(yong)(yong)車(che)(che)(che)選用(yong)(yong)車(che)(che)(che)型目錄(征(zheng)求(qiu)意(yi)見稿(gao))》為(wei)(wei)自主品牌(pai)擴大在政府(fu)采購的(de)市場份額,為(wei)(wei)改變目前國內(nei)政府(fu)采購以(yi)(yi)合資品牌(pai)產(chan)品為(wei)(wei)主的(de)局面提(ti)(ti)(ti)供了保障。促進自主品牌(pai)發展,國產(chan)汽(qi)車(che)(che)(che)業(ye)的(de)繁榮將(jiang)為(wei)(wei)汽(qi)車(che)(che)(che)膠(jiao)的(de)應(ying)用(yong)(yong)提(ti)(ti)(ti)供有(you)力保障。預測未來3年,我(wo)國室溫硫化硅(gui)橡膠(jiao)在汽(qi)車(che)(che)(che)行業(ye)將(jiang)以(yi)(yi)年均20%增(zeng)長。
此外,硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)是重要的(de)(de)非石油(you)(you)基合(he)成(cheng)(cheng)橡(xiang)(xiang)(xiang)膠(jiao),約(yue)占非石油(you)(you)基合(he)成(cheng)(cheng)橡(xiang)(xiang)(xiang)膠(jiao)消費量的(de)(de)98%。但因(yin)為(wei)石油(you)(you)價(jia)格(ge)的(de)(de)大(da)幅上(shang)漲,同時我國在硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)的(de)(de)關鍵原料有(you)機硅(gui)(gui)單體(ti)的(de)(de)生產技術(shu)方(fang)面(mian)取得突破(po),有(you)機硅(gui)(gui)單體(ti)的(de)(de)生產技術(shu)在2005年前(qian)被(bei)幾家跨(kua)國公司(si)壟(long)斷(duan),但目前(qian)我國已發展成(cheng)(cheng)為(wei)全球有(you)機硅(gui)(gui)單體(ti)第1大(da)國,這(zhe)2個方(fang)面(mian)原因(yin)使硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)的(de)(de)價(jia)格(ge)從(cong)2011年起(qi)開始低于(yu)石油(you)(you)基合(he)成(cheng)(cheng)橡(xiang)(xiang)(xiang)膠(jiao),僅約(yue)為(wei)大(da)宗石油(you)(you)基橡(xiang)(xiang)(xiang)膠(jiao)的(de)(de)80%~90%,成(cheng)(cheng)為(wei)廉價(jia)的(de)(de)合(he)成(cheng)(cheng)橡(xiang)(xiang)(xiang)膠(jiao),并(bing)開始大(da)規(gui)模替代石油(you)(you)基合(he)成(cheng)(cheng)橡(xiang)(xiang)(xiang)膠(jiao)。這(zhe)將(jiang)極大(da)拓展有(you)機硅(gui)(gui)產業的(de)(de)市場空(kong)間(jian),同時將(jiang)帶動硅(gui)(gui)油(you)(you)、硅(gui)(gui)烷(wan)偶聯劑(ji)和硅(gui)(gui)樹脂等其他有(you)機硅(gui)(gui)產品的(de)(de)消費。