
硅橡膠是指主鏈由硅(gui)(gui)(gui)(gui)(gui)和氧(yang)原子交(jiao)替構成,硅(gui)(gui)(gui)(gui)(gui)原子上通(tong)常連有(you)兩個有(you)機基(ji)團的(de)(de)橡(xiang)(xiang)膠(jiao)。普通(tong)的(de)(de)硅(gui)(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)主要由含甲(jia)基(ji)和少量乙烯基(ji)的(de)(de)硅(gui)(gui)(gui)(gui)(gui)氧(yang)鏈節組成。苯基(ji)的(de)(de)引(yin)入(ru)可(ke)(ke)提(ti)高(gao)硅(gui)(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)的(de)(de)耐(nai)(nai)高(gao)、低(di)溫性(xing)(xing)(xing)能(neng),三氟丙基(ji)及氰基(ji)的(de)(de)引(yin)入(ru)則可(ke)(ke)提(ti)高(gao)硅(gui)(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)的(de)(de)耐(nai)(nai)溫及耐(nai)(nai)油性(xing)(xing)(xing)能(neng)。硅(gui)(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)耐(nai)(nai)低(di)溫性(xing)(xing)(xing)能(neng)良好(hao)(hao),一(yi)般在-55℃下(xia)仍能(neng)工作。引(yin)入(ru)苯基(ji)后(hou),可(ke)(ke)達-73℃。硅(gui)(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)的(de)(de)耐(nai)(nai)熱性(xing)(xing)(xing)能(neng)也很突出,在180℃下(xia)可(ke)(ke)長期工作,稍高(gao)于(yu)200℃也能(neng)承受(shou)數周或更長時間(jian)仍有(you)彈性(xing)(xing)(xing),瞬時可(ke)(ke)耐(nai)(nai)300℃以上的(de)(de)高(gao)溫。硅(gui)(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)的(de)(de)透氣(qi)性(xing)(xing)(xing)好(hao)(hao),氧(yang)氣(qi)透過率在合(he)成聚合(he)物中是較高(gao)的(de)(de)。此(ci)外,硅(gui)(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)還具有(you)生理惰(duo)性(xing)(xing)(xing)、不會(hui)導(dao)致凝血的(de)(de)突出特性(xing)(xing)(xing),因(yin)此(ci)在醫用(yong)領域(yu)應(ying)用(yong)廣泛。
主要品種
硅(gui)橡(xiang)(xiang)膠(jiao)分(fen)類(lei)的(de)(de)方法很多,通常按(an)固化前的(de)(de)形態分(fen)為(wei)固體硅(gui)橡(xiang)(xiang)膠(jiao)和液體硅(gui)橡(xiang)(xiang)膠(jiao);按(an)硫化溫度分(fen)為(wei)室溫硫化硅(gui)橡(xiang)(xiang)膠(jiao),高溫硫化硅(gui)橡(xiang)(xiang)膠(jiao);按(an)所用(yong)(yong)(yong)單(dan)體的(de)(de)不同,可分(fen)為(wei)甲(jia)基(ji)乙烯(xi)基(ji)硅(gui)橡(xiang)(xiang)膠(jiao),甲(jia)基(ji)苯基(ji)乙烯(xi)基(ji)硅(gui)橡(xiang)(xiang)膠(jiao)、氟硅(gui),腈(jing)硅(gui)橡(xiang)(xiang)膠(jiao)等;按(an)性能和用(yong)(yong)(yong)途(tu)的(de)(de)不同又可分(fen)為(wei)通用(yong)(yong)(yong)型(xing)(xing)(xing)、超(chao)耐低溫型(xing)(xing)(xing)、超(chao)耐高溫型(xing)(xing)(xing)、高強(qiang)力(li)型(xing)(xing)(xing)、耐油型(xing)(xing)(xing)、醫用(yong)(yong)(yong)型(xing)(xing)(xing)等等。
發展史
硅(gui)橡(xiang)(xiang)膠(jiao)早期(qi)是由美(mei)國(guo)(guo)(guo)以三(san)氯(lv)化鐵為催化劑合成(cheng)的(de)。1945年(nian),硅(gui)橡(xiang)(xiang)膠(jiao)產品(pin)問世。1948年(nian),采用(yong)高(gao)比表面積的(de)氣相法白炭(tan)黑補強的(de)硅(gui)橡(xiang)(xiang)膠(jiao)研(yan)制成(cheng)功,使硅(gui)橡(xiang)(xiang)膠(jiao)的(de)性能躍升到(dao)實用(yong)階段,奠定(ding)了現代硅(gui)橡(xiang)(xiang)膠(jiao)生產技術的(de)基礎。從二甲基二氯(lv)硅(gui)烷合成(cheng)開(kai)始(shi)生產硅(gui)橡(xiang)(xiang)膠(jiao)的(de)國(guo)(guo)(guo)家(jia)有美(mei)國(guo)(guo)(guo)。俄羅斯、德國(guo)(guo)(guo)、日本(ben)、韓(han)國(guo)(guo)(guo)和中(zhong)(zhong)國(guo)(guo)(guo)等。中(zhong)(zhong)國(guo)(guo)(guo)硅(gui)橡(xiang)(xiang)膠(jiao)的(de)工業(ye)化研(yan)究(jiu)始(shi)于(yu)1957年(nian),多家(jia)研(yan)究(jiu)所(suo)和企業(ye)陸(lu)續開(kai)發出各種硅(gui)橡(xiang)(xiang)膠(jiao)。到(dao)2003年(nian)底,中(zhong)(zhong)國(guo)(guo)(guo)硅(gui)橡(xiang)(xiang)膠(jiao)生產能力(li)為135千(qian)(qian)噸,其中(zhong)(zhong)高(gao)溫膠(jiao)100千(qian)(qian)噸。
高溫硫化硅橡膠
高(gao)溫硫(liu)(liu)化(hua)硅(gui)橡(xiang)膠(jiao)(jiao)是指(zhi)聚硅(gui)氧烷變(bian)成彈性體的過程是經過高(gao)溫(110-170℃)硫(liu)(liu)化(hua)成型的。它主要(yao)以高(gao)分子量的聚甲基乙烯基硅(gui)氧烷為(wei)生膠(jiao)(jiao),混(hun)入補(bu)強填料、硫(liu)(liu)化(hua)劑等,在加(jia)(jia)熱加(jia)(jia)壓下硫(liu)(liu)化(hua)成彈性體。硅(gui)橡(xiang)膠(jiao)(jiao)的補(bu)強主要(yao)是各種類型的白炭黑(hei),可使硫(liu)(liu)化(hua)膠(jiao)(jiao)的強度增加(jia)(jia)數十倍。有(you)時(shi)為(wei)了降低成本或(huo)(huo)改善(shan)膠(jiao)(jiao)料性能(neng)及賦(fu)予硫(liu)(liu)化(hua)膠(jiao)(jiao)各種特殊的性能(neng),也(ye)加(jia)(jia)入相應的各種添(tian)加(jia)(jia)劑。硫(liu)(liu)化(hua)劑是各種有(you)機(ji)過氧化(hua)物或(huo)(huo)加(jia)(jia)成反應催化(hua)劑。
加工成型(xing)方法(fa)如圖所(suo)示。一(yi)次(ci)(ci)硫(liu)化(hua)(hua)的目的是(shi)(shi)進行(xing)高分(fen)子鏈的交聯反應;二(er)次(ci)(ci)硫(liu)化(hua)(hua)的目的是(shi)(shi)進行(xing)補充(chong)交聯、驅除(chu)硫(liu)化(hua)(hua)劑(ji)分(fen)解產物和其(qi)他(ta)揮發性化(hua)(hua)合物以穩定硫(liu)化(hua)(hua)膠的各項性能(neng)。常用的設(she)備有開(kai)放式煉膠機(ji)、捏合機(ji)及真(zhen)空(kong)密煉機(ji)。
主要性能
(1)高溫(wen)(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)。硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)顯著的(de)(de)(de)特征是(shi)高溫(wen)(wen)(wen)穩定性(xing)(xing)(xing)(xing)(xing)(xing),雖然常(chang)溫(wen)(wen)(wen)下(xia)硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)的(de)(de)(de)強(qiang)度僅是(shi)天然橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)或(huo)某些合成橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)的(de)(de)(de)一半(ban),但在200℃以上(shang)的(de)(de)(de)高溫(wen)(wen)(wen)環境下(xia),硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)仍能(neng)(neng)保持一定的(de)(de)(de)柔韌性(xing)(xing)(xing)(xing)(xing)(xing)、回彈性(xing)(xing)(xing)(xing)(xing)(xing)和(he)(he)表(biao)面硬度,且力學(xue)性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)無(wu)明(ming)顯變化。(2)低溫(wen)(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)的(de)(de)(de)玻璃化溫(wen)(wen)(wen)度一般(ban)為(wei)-70~-50℃,特殊配(pei)方可達-100℃,表(biao)明(ming)其(qi)(qi)低溫(wen)(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)優(you)(you)異。這對(dui)航(hang)空、宇航(hang)工業的(de)(de)(de)意義重大(da)。(3)耐候(hou)性(xing)(xing)(xing)(xing)(xing)(xing)硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)中Si-O-Si鍵對(dui)氧(yang)、臭(chou)氧(yang)及(ji)紫外(wai)線等(deng)十分(fen)穩定,在不加任(ren)何(he)添(tian)加劑的(de)(de)(de)情況下(xia),就具(ju)(ju)有(you)(you)(you)優(you)(you)良的(de)(de)(de)耐候(hou)性(xing)(xing)(xing)(xing)(xing)(xing)。(4)電氣(qi)性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)。硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)具(ju)(ju)有(you)(you)(you)優(you)(you)異的(de)(de)(de)絕緣性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng),耐電暈性(xing)(xing)(xing)(xing)(xing)(xing)和(he)(he)耐電弧性(xing)(xing)(xing)(xing)(xing)(xing)也非常(chang)好(hao)。(5)物(wu)理(li)(li)機械(xie)性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)。硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)常(chang)溫(wen)(wen)(wen)下(xia)的(de)(de)(de)物(wu)理(li)(li)機械(xie)性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)比通用(yong)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)差,但在150℃的(de)(de)(de)高溫(wen)(wen)(wen)和(he)(he)-50℃的(de)(de)(de)低溫(wen)(wen)(wen)下(xia),其(qi)(qi)物(wu)理(li)(li)機械(xie)性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)優(you)(you)于(yu)通用(yong)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)。(6)耐油(you)及(ji)化學(xue)試劑性(xing)(xing)(xing)(xing)(xing)(xing)。普(pu)通硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)具(ju)(ju)有(you)(you)(you)中等(deng)的(de)(de)(de)耐油(you)、耐溶劑性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)。(7)氣(qi)體透過性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)。室溫(wen)(wen)(wen)下(xia)硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)對(dui)空氣(qi)、氮、氧(yang)、二氧(yang)化碳等(deng)氣(qi)體的(de)(de)(de)透氣(qi)性(xing)(xing)(xing)(xing)(xing)(xing)比天然橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)高出30-50倍。(8)生理(li)(li)惰性(xing)(xing)(xing)(xing)(xing)(xing)。硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)無(wu)毒,無(wu)味,無(wu)嗅(xiu),與人體組(zu)織(zhi)不粘連,具(ju)(ju)有(you)(you)(you)抗凝(ning)血作(zuo)用(yong),對(dui)肌(ji)體組(zu)織(zhi)的(de)(de)(de)反應性(xing)(xing)(xing)(xing)(xing)(xing)非常(chang)少。特別適(shi)合作(zuo)為(wei)醫用(yong)材料。
硅橡膠的用量
據中國(guo)汽(qi)(qi)車(che)工(gong)業(ye)協會統計,2012年(nian),汽(qi)(qi)車(che)產(chan)銷(xiao)分別達(da)到1927.18萬(wan)(wan)輛和1930.64萬(wan)(wan)輛,同比分別增長4.63%和4.33%,汽(qi)(qi)車(che)工(gong)業(ye)硅(gui)橡(xiang)膠(jiao)的(de)(de)(de)用(yong)(yong)量約達(da)2.0萬(wan)(wan)t。根據觀研(yan)(yan)天下的(de)(de)(de)新研(yan)(yan)究(jiu),增加有機硅(gui)材料在汽(qi)(qi)車(che)零部(bu)件方(fang)面(mian)的(de)(de)(de)用(yong)(yong)量,可(ke)以(yi)大幅(fu)度提(ti)高汽(qi)(qi)車(che)的(de)(de)(de)安全性能,因此,汽(qi)(qi)車(che)產(chan)量和單(dan)車(che)用(yong)(yong)量水平的(de)(de)(de)提(ti)高都將(jiang)(jiang)推動汽(qi)(qi)車(che)工(gong)業(ye)對硅(gui)橡(xiang)膠(jiao)需求的(de)(de)(de)增加。國(guo)家鼓勵自主(zhu)品牌的(de)(de)(de)汽(qi)(qi)車(che)發展(zhan),關(guan)鍵汽(qi)(qi)車(che)零部(bu)件實現(xian)自主(zhu)化(hua),《2012年(nian)度黨政機關(guan)公(gong)務用(yong)(yong)車(che)選用(yong)(yong)車(che)型目錄(征求意見稿)》為自主(zhu)品牌擴大在政府采購的(de)(de)(de)市場(chang)份額,為改變(bian)目前(qian)國(guo)內(nei)政府采購以(yi)合(he)資品牌產(chan)品為主(zhu)的(de)(de)(de)局面(mian)提(ti)供了保障。促進自主(zhu)品牌發展(zhan),國(guo)產(chan)汽(qi)(qi)車(che)業(ye)的(de)(de)(de)繁(fan)榮將(jiang)(jiang)為汽(qi)(qi)車(che)膠(jiao)的(de)(de)(de)應用(yong)(yong)提(ti)供有力保障。預(yu)測未(wei)來3年(nian),我(wo)國(guo)室溫(wen)硫化(hua)硅(gui)橡(xiang)膠(jiao)在汽(qi)(qi)車(che)行業(ye)將(jiang)(jiang)以(yi)年(nian)均20%增長。
此外,硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)是重要的非(fei)(fei)石(shi)(shi)油基(ji)合(he)(he)成(cheng)(cheng)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao),約占非(fei)(fei)石(shi)(shi)油基(ji)合(he)(he)成(cheng)(cheng)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)消費量的98%。但(dan)因(yin)為(wei)石(shi)(shi)油價格的大(da)幅上漲(zhang),同時(shi)我(wo)國(guo)在硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)的關(guan)鍵原料(liao)有(you)(you)機硅(gui)(gui)單體(ti)的生產(chan)技術(shu)方面(mian)取得突破,有(you)(you)機硅(gui)(gui)單體(ti)的生產(chan)技術(shu)在2005年前(qian)被(bei)幾家跨國(guo)公司壟斷(duan),但(dan)目(mu)前(qian)我(wo)國(guo)已發展(zhan)成(cheng)(cheng)為(wei)全(quan)球有(you)(you)機硅(gui)(gui)單體(ti)第1大(da)國(guo),這(zhe)2個方面(mian)原因(yin)使硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)的價格從2011年起開始(shi)低于石(shi)(shi)油基(ji)合(he)(he)成(cheng)(cheng)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao),僅約為(wei)大(da)宗石(shi)(shi)油基(ji)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)的80%~90%,成(cheng)(cheng)為(wei)廉(lian)價的合(he)(he)成(cheng)(cheng)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao),并開始(shi)大(da)規模替(ti)代石(shi)(shi)油基(ji)合(he)(he)成(cheng)(cheng)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)。這(zhe)將(jiang)極大(da)拓(tuo)展(zhan)有(you)(you)機硅(gui)(gui)產(chan)業的市場空間,同時(shi)將(jiang)帶(dai)動硅(gui)(gui)油、硅(gui)(gui)烷偶聯劑和硅(gui)(gui)樹(shu)脂等(deng)其他有(you)(you)機硅(gui)(gui)產(chan)品的消費。