
硅橡膠是(shi)指主鏈由硅(gui)(gui)(gui)(gui)和氧原子(zi)交(jiao)替構成(cheng)(cheng),硅(gui)(gui)(gui)(gui)原子(zi)上通常連有兩個(ge)有機(ji)基(ji)(ji)團的(de)(de)(de)(de)橡(xiang)(xiang)膠。普(pu)通的(de)(de)(de)(de)硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠主要由含甲(jia)基(ji)(ji)和少(shao)量(liang)乙烯(xi)基(ji)(ji)的(de)(de)(de)(de)硅(gui)(gui)(gui)(gui)氧鏈節組成(cheng)(cheng)。苯基(ji)(ji)的(de)(de)(de)(de)引(yin)入(ru)(ru)可(ke)(ke)(ke)提高(gao)硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠的(de)(de)(de)(de)耐高(gao)、低溫性(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng),三氟(fu)丙基(ji)(ji)及(ji)氰基(ji)(ji)的(de)(de)(de)(de)引(yin)入(ru)(ru)則可(ke)(ke)(ke)提高(gao)硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠的(de)(de)(de)(de)耐溫及(ji)耐油(you)性(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)。硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠耐低溫性(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)良好,一般(ban)在-55℃下(xia)仍能(neng)(neng)(neng)(neng)(neng)工作(zuo)。引(yin)入(ru)(ru)苯基(ji)(ji)后(hou),可(ke)(ke)(ke)達-73℃。硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠的(de)(de)(de)(de)耐熱性(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)也(ye)很(hen)突(tu)出,在180℃下(xia)可(ke)(ke)(ke)長期工作(zuo),稍高(gao)于200℃也(ye)能(neng)(neng)(neng)(neng)(neng)承受數周(zhou)或更(geng)長時(shi)間仍有彈(dan)性(xing)(xing)(xing),瞬時(shi)可(ke)(ke)(ke)耐300℃以上的(de)(de)(de)(de)高(gao)溫。硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠的(de)(de)(de)(de)透氣性(xing)(xing)(xing)好,氧氣透過率在合成(cheng)(cheng)聚(ju)合物中是(shi)較高(gao)的(de)(de)(de)(de)。此外,硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠還(huan)具有生理惰性(xing)(xing)(xing)、不(bu)會導(dao)致凝(ning)血(xue)的(de)(de)(de)(de)突(tu)出特性(xing)(xing)(xing),因此在醫用(yong)領域應用(yong)廣泛。
主要品種(zhong)
硅(gui)(gui)橡膠分(fen)類的方(fang)法(fa)很多,通(tong)常按(an)(an)固化(hua)(hua)前的形態分(fen)為固體(ti)硅(gui)(gui)橡膠和液體(ti)硅(gui)(gui)橡膠;按(an)(an)硫化(hua)(hua)溫(wen)(wen)度分(fen)為室溫(wen)(wen)硫化(hua)(hua)硅(gui)(gui)橡膠,高(gao)溫(wen)(wen)硫化(hua)(hua)硅(gui)(gui)橡膠;按(an)(an)所(suo)用(yong)單體(ti)的不同,可(ke)分(fen)為甲(jia)基(ji)(ji)乙(yi)烯基(ji)(ji)硅(gui)(gui)橡膠,甲(jia)基(ji)(ji)苯基(ji)(ji)乙(yi)烯基(ji)(ji)硅(gui)(gui)橡膠、氟硅(gui)(gui),腈硅(gui)(gui)橡膠等;按(an)(an)性(xing)能(neng)和用(yong)途的不同又可(ke)分(fen)為通(tong)用(yong)型、超耐(nai)低(di)溫(wen)(wen)型、超耐(nai)高(gao)溫(wen)(wen)型、高(gao)強力(li)型、耐(nai)油型、醫用(yong)型等等。
發展(zhan)史
硅(gui)(gui)橡(xiang)膠(jiao)早期(qi)是由美國(guo)以三氯(lv)化(hua)鐵為(wei)催化(hua)劑合成(cheng)(cheng)的。1945年,硅(gui)(gui)橡(xiang)膠(jiao)產品(pin)問(wen)世。1948年,采用高比(bi)表面積的氣相法白炭(tan)黑補強的硅(gui)(gui)橡(xiang)膠(jiao)研(yan)(yan)制成(cheng)(cheng)功,使硅(gui)(gui)橡(xiang)膠(jiao)的性能躍(yue)升(sheng)到實用階段(duan),奠定了(le)現(xian)代硅(gui)(gui)橡(xiang)膠(jiao)生(sheng)產技術的基礎(chu)。從(cong)二甲基二氯(lv)硅(gui)(gui)烷合成(cheng)(cheng)開(kai)始(shi)生(sheng)產硅(gui)(gui)橡(xiang)膠(jiao)的國(guo)家(jia)有美國(guo)。俄羅(luo)斯、德國(guo)、日本(ben)、韓國(guo)和(he)中國(guo)等。中國(guo)硅(gui)(gui)橡(xiang)膠(jiao)的工(gong)業(ye)化(hua)研(yan)(yan)究始(shi)于1957年,多家(jia)研(yan)(yan)究所和(he)企(qi)業(ye)陸續開(kai)發出各種硅(gui)(gui)橡(xiang)膠(jiao)。到2003年底,中國(guo)硅(gui)(gui)橡(xiang)膠(jiao)生(sheng)產能力為(wei)135千(qian)(qian)噸(dun),其(qi)中高溫膠(jiao)100千(qian)(qian)噸(dun)。
高溫硫化(hua)硅橡(xiang)膠
高(gao)溫硫(liu)化(hua)(hua)(hua)硅橡膠是指聚(ju)硅氧(yang)烷變成(cheng)彈(dan)性(xing)體(ti)的(de)過程是經過高(gao)溫(110-170℃)硫(liu)化(hua)(hua)(hua)成(cheng)型(xing)的(de)。它(ta)主要以高(gao)分子量(liang)的(de)聚(ju)甲基乙烯(xi)基硅氧(yang)烷為生(sheng)膠,混入補強(qiang)(qiang)填料、硫(liu)化(hua)(hua)(hua)劑等(deng),在加(jia)熱加(jia)壓下(xia)硫(liu)化(hua)(hua)(hua)成(cheng)彈(dan)性(xing)體(ti)。硅橡膠的(de)補強(qiang)(qiang)主要是各種(zhong)(zhong)類型(xing)的(de)白炭黑,可使硫(liu)化(hua)(hua)(hua)膠的(de)強(qiang)(qiang)度增加(jia)數十倍。有(you)時為了降低(di)成(cheng)本(ben)或改善(shan)膠料性(xing)能(neng)及賦予(yu)硫(liu)化(hua)(hua)(hua)膠各種(zhong)(zhong)特(te)殊的(de)性(xing)能(neng),也(ye)加(jia)入相應的(de)各種(zhong)(zhong)添加(jia)劑。硫(liu)化(hua)(hua)(hua)劑是各種(zhong)(zhong)有(you)機過氧(yang)化(hua)(hua)(hua)物或加(jia)成(cheng)反(fan)應催化(hua)(hua)(hua)劑。
加工成型方(fang)法(fa)如圖所示(shi)。一次硫(liu)化的(de)目的(de)是(shi)進行高分子鏈的(de)交(jiao)聯(lian)反應;二(er)次硫(liu)化的(de)目的(de)是(shi)進行補充(chong)交(jiao)聯(lian)、驅除硫(liu)化劑分解產物和其他揮(hui)發性化合(he)物以穩定硫(liu)化膠的(de)各項性能。常用的(de)設備有開放式煉膠機、捏合(he)機及真空(kong)密煉機。
主(zhu)要(yao)性能
(1)高(gao)(gao)(gao)溫(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)。硅(gui)橡(xiang)(xiang)膠(jiao)(jiao)顯著的(de)(de)(de)特(te)征是高(gao)(gao)(gao)溫(wen)(wen)穩定性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing),雖(sui)然(ran)常(chang)溫(wen)(wen)下(xia)硅(gui)橡(xiang)(xiang)膠(jiao)(jiao)的(de)(de)(de)強度(du)(du)僅(jin)是天(tian)然(ran)橡(xiang)(xiang)膠(jiao)(jiao)或某些合(he)成橡(xiang)(xiang)膠(jiao)(jiao)的(de)(de)(de)一半,但在200℃以上的(de)(de)(de)高(gao)(gao)(gao)溫(wen)(wen)環境下(xia),硅(gui)橡(xiang)(xiang)膠(jiao)(jiao)仍能(neng)保持一定的(de)(de)(de)柔韌性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)、回彈性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)和表面硬度(du)(du),且力學性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)無(wu)(wu)(wu)明(ming)顯變化(hua)(hua)。(2)低(di)溫(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)硅(gui)橡(xiang)(xiang)膠(jiao)(jiao)的(de)(de)(de)玻(bo)璃化(hua)(hua)溫(wen)(wen)度(du)(du)一般為-70~-50℃,特(te)殊配方可達-100℃,表明(ming)其(qi)低(di)溫(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)優(you)(you)異(yi)。這對航(hang)空(kong)、宇(yu)航(hang)工(gong)業的(de)(de)(de)意義(yi)重大(da)。(3)耐(nai)候性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)硅(gui)橡(xiang)(xiang)膠(jiao)(jiao)中(zhong)Si-O-Si鍵(jian)對氧(yang)、臭氧(yang)及(ji)紫外線等(deng)十分穩定,在不加(jia)任(ren)何添加(jia)劑的(de)(de)(de)情況(kuang)下(xia),就(jiu)具(ju)有(you)(you)(you)優(you)(you)良的(de)(de)(de)耐(nai)候性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)。(4)電氣(qi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)。硅(gui)橡(xiang)(xiang)膠(jiao)(jiao)具(ju)有(you)(you)(you)優(you)(you)異(yi)的(de)(de)(de)絕緣性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng),耐(nai)電暈性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)和耐(nai)電弧性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)也非(fei)常(chang)好(hao)。(5)物(wu)理(li)機械性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)。硅(gui)橡(xiang)(xiang)膠(jiao)(jiao)常(chang)溫(wen)(wen)下(xia)的(de)(de)(de)物(wu)理(li)機械性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)比通(tong)用橡(xiang)(xiang)膠(jiao)(jiao)差,但在150℃的(de)(de)(de)高(gao)(gao)(gao)溫(wen)(wen)和-50℃的(de)(de)(de)低(di)溫(wen)(wen)下(xia),其(qi)物(wu)理(li)機械性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)優(you)(you)于(yu)通(tong)用橡(xiang)(xiang)膠(jiao)(jiao)。(6)耐(nai)油及(ji)化(hua)(hua)學試劑性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)。普通(tong)硅(gui)橡(xiang)(xiang)膠(jiao)(jiao)具(ju)有(you)(you)(you)中(zhong)等(deng)的(de)(de)(de)耐(nai)油、耐(nai)溶劑性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)。(7)氣(qi)體(ti)(ti)透過性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)。室(shi)溫(wen)(wen)下(xia)硅(gui)橡(xiang)(xiang)膠(jiao)(jiao)對空(kong)氣(qi)、氮、氧(yang)、二氧(yang)化(hua)(hua)碳等(deng)氣(qi)體(ti)(ti)的(de)(de)(de)透氣(qi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)比天(tian)然(ran)橡(xiang)(xiang)膠(jiao)(jiao)高(gao)(gao)(gao)出30-50倍。(8)生理(li)惰性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)。硅(gui)橡(xiang)(xiang)膠(jiao)(jiao)無(wu)(wu)(wu)毒,無(wu)(wu)(wu)味,無(wu)(wu)(wu)嗅(xiu),與人體(ti)(ti)組(zu)織不粘連,具(ju)有(you)(you)(you)抗凝血(xue)作(zuo)用,對肌(ji)體(ti)(ti)組(zu)織的(de)(de)(de)反應(ying)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)非(fei)常(chang)少(shao)。特(te)別適合(he)作(zuo)為醫(yi)用材料。
硅橡膠的(de)用量
據中國(guo)(guo)(guo)汽(qi)(qi)(qi)車(che)工(gong)業(ye)協會統計(ji),2012年(nian),汽(qi)(qi)(qi)車(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(chang)4.63%和4.33%,汽(qi)(qi)(qi)車(che)工(gong)業(ye)硅(gui)(gui)(gui)橡膠(jiao)的(de)(de)用(yong)量(liang)約達(da)2.0萬(wan)t。根據觀研天(tian)下的(de)(de)新(xin)研究,增加有機(ji)(ji)硅(gui)(gui)(gui)材料在(zai)汽(qi)(qi)(qi)車(che)零(ling)部(bu)(bu)件方面的(de)(de)用(yong)量(liang),可(ke)以(yi)大(da)幅(fu)度(du)提(ti)高汽(qi)(qi)(qi)車(che)的(de)(de)安全性(xing)能,因(yin)此,汽(qi)(qi)(qi)車(che)產量(liang)和單車(che)用(yong)量(liang)水平的(de)(de)提(ti)高都(dou)將(jiang)推動汽(qi)(qi)(qi)車(che)工(gong)業(ye)對(dui)硅(gui)(gui)(gui)橡膠(jiao)需求(qiu)的(de)(de)增加。國(guo)(guo)(guo)家鼓勵自(zi)(zi)主(zhu)(zhu)品牌(pai)的(de)(de)汽(qi)(qi)(qi)車(che)發展(zhan),關鍵汽(qi)(qi)(qi)車(che)零(ling)部(bu)(bu)件實(shi)現自(zi)(zi)主(zhu)(zhu)化,《2012年(nian)度(du)黨政機(ji)(ji)關公(gong)務用(yong)車(che)選(xuan)用(yong)車(che)型目錄(征(zheng)求(qiu)意見稿)》為(wei)自(zi)(zi)主(zhu)(zhu)品牌(pai)擴大(da)在(zai)政府(fu)采購的(de)(de)市場份額,為(wei)改(gai)變目前國(guo)(guo)(guo)內政府(fu)采購以(yi)合資品牌(pai)產品為(wei)主(zhu)(zhu)的(de)(de)局(ju)面提(ti)供(gong)了(le)保(bao)障(zhang)。促進(jin)自(zi)(zi)主(zhu)(zhu)品牌(pai)發展(zhan),國(guo)(guo)(guo)產汽(qi)(qi)(qi)車(che)業(ye)的(de)(de)繁(fan)榮將(jiang)為(wei)汽(qi)(qi)(qi)車(che)膠(jiao)的(de)(de)應用(yong)提(ti)供(gong)有力保(bao)障(zhang)。預測未來3年(nian),我國(guo)(guo)(guo)室(shi)溫(wen)硫化硅(gui)(gui)(gui)橡膠(jiao)在(zai)汽(qi)(qi)(qi)車(che)行業(ye)將(jiang)以(yi)年(nian)均20%增長(chang)。
此外,硅(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao)是(shi)重(zhong)要(yao)的(de)(de)(de)(de)非(fei)石油(you)(you)基合成(cheng)橡(xiang)膠(jiao)(jiao)(jiao),約占非(fei)石油(you)(you)基合成(cheng)橡(xiang)膠(jiao)(jiao)(jiao)消費量(liang)的(de)(de)(de)(de)98%。但因為(wei)石油(you)(you)價格(ge)的(de)(de)(de)(de)大幅上(shang)漲,同(tong)時我(wo)國在硅(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao)的(de)(de)(de)(de)關鍵原料有(you)機(ji)硅(gui)(gui)(gui)單體的(de)(de)(de)(de)生(sheng)產(chan)(chan)技術方面(mian)取得突破,有(you)機(ji)硅(gui)(gui)(gui)單體的(de)(de)(de)(de)生(sheng)產(chan)(chan)技術在2005年(nian)前被幾(ji)家跨(kua)國公司壟斷,但目前我(wo)國已發展成(cheng)為(wei)全球有(you)機(ji)硅(gui)(gui)(gui)單體第1大國,這(zhe)2個(ge)方面(mian)原因使硅(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao)的(de)(de)(de)(de)價格(ge)從(cong)2011年(nian)起開始低(di)于石油(you)(you)基合成(cheng)橡(xiang)膠(jiao)(jiao)(jiao),僅約為(wei)大宗(zong)石油(you)(you)基橡(xiang)膠(jiao)(jiao)(jiao)的(de)(de)(de)(de)80%~90%,成(cheng)為(wei)廉價的(de)(de)(de)(de)合成(cheng)橡(xiang)膠(jiao)(jiao)(jiao),并(bing)開始大規模替代石油(you)(you)基合成(cheng)橡(xiang)膠(jiao)(jiao)(jiao)。這(zhe)將極大拓(tuo)展有(you)機(ji)硅(gui)(gui)(gui)產(chan)(chan)業的(de)(de)(de)(de)市場空間,同(tong)時將帶(dai)動硅(gui)(gui)(gui)油(you)(you)、硅(gui)(gui)(gui)烷偶聯劑和硅(gui)(gui)(gui)樹(shu)脂等其他有(you)機(ji)硅(gui)(gui)(gui)產(chan)(chan)品的(de)(de)(de)(de)消費。