硅橡膠是(shi)指主鏈(lian)由(you)硅(gui)和氧(yang)(yang)原子交(jiao)替構(gou)成(cheng),硅(gui)原子上通常(chang)連有(you)兩個(ge)有(you)機基團的(de)橡(xiang)(xiang)(xiang)膠(jiao)。普通的(de)硅(gui)橡(xiang)(xiang)(xiang)膠(jiao)主要由(you)含甲基和少(shao)量乙烯基的(de)硅(gui)氧(yang)(yang)鏈(lian)節組成(cheng)。苯(ben)基的(de)引(yin)入(ru)可(ke)提高(gao)硅(gui)橡(xiang)(xiang)(xiang)膠(jiao)的(de)耐(nai)高(gao)、低溫性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng),三(san)氟(fu)丙基及氰(qing)基的(de)引(yin)入(ru)則可(ke)提高(gao)硅(gui)橡(xiang)(xiang)(xiang)膠(jiao)的(de)耐(nai)溫及耐(nai)油性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)。硅(gui)橡(xiang)(xiang)(xiang)膠(jiao)耐(nai)低溫性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)良(liang)好(hao),一般在-55℃下仍能(neng)(neng)工(gong)作。引(yin)入(ru)苯(ben)基后,可(ke)達-73℃。硅(gui)橡(xiang)(xiang)(xiang)膠(jiao)的(de)耐(nai)熱性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)也(ye)很(hen)突(tu)出(chu),在180℃下可(ke)長期工(gong)作,稍高(gao)于200℃也(ye)能(neng)(neng)承受數周(zhou)或更(geng)長時(shi)間仍有(you)彈性(xing)(xing)(xing)(xing)(xing)(xing),瞬時(shi)可(ke)耐(nai)300℃以上的(de)高(gao)溫。硅(gui)橡(xiang)(xiang)(xiang)膠(jiao)的(de)透氣性(xing)(xing)(xing)(xing)(xing)(xing)好(hao),氧(yang)(yang)氣透過率在合(he)成(cheng)聚合(he)物中是(shi)較高(gao)的(de)。此外,硅(gui)橡(xiang)(xiang)(xiang)膠(jiao)還具有(you)生理惰性(xing)(xing)(xing)(xing)(xing)(xing)、不會導致凝血的(de)突(tu)出(chu)特性(xing)(xing)(xing)(xing)(xing)(xing),因此在醫用領(ling)域應(ying)用廣(guang)泛(fan)。
主要品種
硅(gui)(gui)(gui)(gui)橡(xiang)膠分(fen)(fen)(fen)類(lei)的(de)方法很(hen)多(duo),通常(chang)按(an)固化前的(de)形(xing)態(tai)分(fen)(fen)(fen)為固體(ti)(ti)硅(gui)(gui)(gui)(gui)橡(xiang)膠和液體(ti)(ti)硅(gui)(gui)(gui)(gui)橡(xiang)膠;按(an)硫(liu)化溫(wen)度(du)分(fen)(fen)(fen)為室溫(wen)硫(liu)化硅(gui)(gui)(gui)(gui)橡(xiang)膠,高(gao)溫(wen)硫(liu)化硅(gui)(gui)(gui)(gui)橡(xiang)膠;按(an)所用單體(ti)(ti)的(de)不同,可(ke)分(fen)(fen)(fen)為甲基(ji)乙(yi)烯(xi)基(ji)硅(gui)(gui)(gui)(gui)橡(xiang)膠,甲基(ji)苯基(ji)乙(yi)烯(xi)基(ji)硅(gui)(gui)(gui)(gui)橡(xiang)膠、氟硅(gui)(gui)(gui)(gui),腈(jing)硅(gui)(gui)(gui)(gui)橡(xiang)膠等;按(an)性能(neng)和用途的(de)不同又可(ke)分(fen)(fen)(fen)為通用型(xing)、超耐低溫(wen)型(xing)、超耐高(gao)溫(wen)型(xing)、高(gao)強力型(xing)、耐油型(xing)、醫用型(xing)等等。
發展史
硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)早期是由美(mei)國(guo)(guo)(guo)以(yi)三氯(lv)化鐵為(wei)催化劑合成的(de)(de)(de)。1945年(nian)(nian)(nian),硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)產品問世。1948年(nian)(nian)(nian),采用(yong)高比表面積的(de)(de)(de)氣(qi)相法白炭黑(hei)補強的(de)(de)(de)硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)研(yan)(yan)制(zhi)成功,使硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)的(de)(de)(de)性能躍升到(dao)實用(yong)階段(duan),奠定(ding)了(le)現代硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)生產技(ji)術的(de)(de)(de)基(ji)礎。從二甲基(ji)二氯(lv)硅(gui)(gui)烷合成開始(shi)生產硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)的(de)(de)(de)國(guo)(guo)(guo)家(jia)有美(mei)國(guo)(guo)(guo)。俄羅斯、德國(guo)(guo)(guo)、日本、韓國(guo)(guo)(guo)和(he)中國(guo)(guo)(guo)等。中國(guo)(guo)(guo)硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)的(de)(de)(de)工業(ye)(ye)化研(yan)(yan)究(jiu)始(shi)于1957年(nian)(nian)(nian),多家(jia)研(yan)(yan)究(jiu)所和(he)企業(ye)(ye)陸續(xu)開發出(chu)各種硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)。到(dao)2003年(nian)(nian)(nian)底,中國(guo)(guo)(guo)硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)生產能力(li)為(wei)135千噸(dun),其中高溫(wen)膠(jiao)(jiao)(jiao)(jiao)(jiao)100千噸(dun)。
高溫硫化硅橡膠
高溫(wen)硫(liu)(liu)化(hua)硅(gui)橡(xiang)膠(jiao)是指聚(ju)硅(gui)氧(yang)(yang)(yang)烷(wan)變成(cheng)(cheng)(cheng)彈性(xing)體(ti)的(de)過程(cheng)是經過高溫(wen)(110-170℃)硫(liu)(liu)化(hua)成(cheng)(cheng)(cheng)型的(de)。它(ta)主要(yao)(yao)以高分子(zi)量的(de)聚(ju)甲基(ji)乙烯基(ji)硅(gui)氧(yang)(yang)(yang)烷(wan)為生(sheng)膠(jiao),混(hun)入補(bu)強填料、硫(liu)(liu)化(hua)劑(ji)(ji)(ji)等,在加(jia)熱加(jia)壓下(xia)硫(liu)(liu)化(hua)成(cheng)(cheng)(cheng)彈性(xing)體(ti)。硅(gui)橡(xiang)膠(jiao)的(de)補(bu)強主要(yao)(yao)是各種(zhong)(zhong)類型的(de)白炭黑,可(ke)使硫(liu)(liu)化(hua)膠(jiao)的(de)強度(du)增加(jia)數(shu)十倍。有(you)時(shi)為了降(jiang)低成(cheng)(cheng)(cheng)本或改善膠(jiao)料性(xing)能(neng)及賦予(yu)硫(liu)(liu)化(hua)膠(jiao)各種(zhong)(zhong)特殊的(de)性(xing)能(neng),也加(jia)入相應的(de)各種(zhong)(zhong)添加(jia)劑(ji)(ji)(ji)。硫(liu)(liu)化(hua)劑(ji)(ji)(ji)是各種(zhong)(zhong)有(you)機(ji)過氧(yang)(yang)(yang)化(hua)物或加(jia)成(cheng)(cheng)(cheng)反應催化(hua)劑(ji)(ji)(ji)。
加工成(cheng)型方法如圖所(suo)示。一次(ci)硫(liu)化(hua)的(de)(de)(de)目(mu)(mu)的(de)(de)(de)是進行(xing)高分子鏈的(de)(de)(de)交聯(lian)反(fan)應;二次(ci)硫(liu)化(hua)的(de)(de)(de)目(mu)(mu)的(de)(de)(de)是進行(xing)補充交聯(lian)、驅除硫(liu)化(hua)劑(ji)分解產(chan)物(wu)和其他揮發性化(hua)合(he)物(wu)以(yi)穩(wen)定硫(liu)化(hua)膠(jiao)的(de)(de)(de)各項(xiang)性能。常用(yong)的(de)(de)(de)設備有開放式煉膠(jiao)機、捏(nie)合(he)機及真空密煉機。
主要性能
(1)高(gao)(gao)溫(wen)(wen)性(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)。硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)顯著的(de)(de)(de)(de)特征(zheng)是高(gao)(gao)溫(wen)(wen)穩定(ding)性(xing)(xing)(xing)(xing),雖(sui)然(ran)常溫(wen)(wen)下(xia)(xia)硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)的(de)(de)(de)(de)強(qiang)度(du)僅是天然(ran)橡(xiang)(xiang)膠(jiao)(jiao)或某些(xie)合成橡(xiang)(xiang)膠(jiao)(jiao)的(de)(de)(de)(de)一半,但在(zai)200℃以上的(de)(de)(de)(de)高(gao)(gao)溫(wen)(wen)環(huan)境下(xia)(xia),硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)仍能(neng)(neng)(neng)(neng)(neng)保持(chi)一定(ding)的(de)(de)(de)(de)柔韌性(xing)(xing)(xing)(xing)、回彈性(xing)(xing)(xing)(xing)和(he)(he)表面硬度(du),且(qie)力學(xue)性(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)無明(ming)顯變化(hua)。(2)低溫(wen)(wen)性(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)的(de)(de)(de)(de)玻璃化(hua)溫(wen)(wen)度(du)一般(ban)為(wei)-70~-50℃,特殊配方可達-100℃,表明(ming)其低溫(wen)(wen)性(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)優(you)(you)異。這(zhe)對航空、宇(yu)航工業的(de)(de)(de)(de)意(yi)義重大。(3)耐候性(xing)(xing)(xing)(xing)硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)中(zhong)Si-O-Si鍵對氧、臭(chou)氧及紫外線等十分(fen)穩定(ding),在(zai)不(bu)加任何添加劑的(de)(de)(de)(de)情(qing)況(kuang)下(xia)(xia),就(jiu)具有(you)優(you)(you)良的(de)(de)(de)(de)耐候性(xing)(xing)(xing)(xing)。(4)電(dian)氣(qi)(qi)性(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)。硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)具有(you)優(you)(you)異的(de)(de)(de)(de)絕緣性(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng),耐電(dian)暈性(xing)(xing)(xing)(xing)和(he)(he)耐電(dian)弧性(xing)(xing)(xing)(xing)也(ye)非常好(hao)。(5)物理(li)機械(xie)性(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)。硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)常溫(wen)(wen)下(xia)(xia)的(de)(de)(de)(de)物理(li)機械(xie)性(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)比通用(yong)橡(xiang)(xiang)膠(jiao)(jiao)差,但在(zai)150℃的(de)(de)(de)(de)高(gao)(gao)溫(wen)(wen)和(he)(he)-50℃的(de)(de)(de)(de)低溫(wen)(wen)下(xia)(xia),其物理(li)機械(xie)性(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)優(you)(you)于通用(yong)橡(xiang)(xiang)膠(jiao)(jiao)。(6)耐油及化(hua)學(xue)試劑性(xing)(xing)(xing)(xing)。普通硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)具有(you)中(zhong)等的(de)(de)(de)(de)耐油、耐溶劑性(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)。(7)氣(qi)(qi)體透過性(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)(neng)。室(shi)溫(wen)(wen)下(xia)(xia)硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)對空氣(qi)(qi)、氮、氧、二氧化(hua)碳(tan)等氣(qi)(qi)體的(de)(de)(de)(de)透氣(qi)(qi)性(xing)(xing)(xing)(xing)比天然(ran)橡(xiang)(xiang)膠(jiao)(jiao)高(gao)(gao)出30-50倍。(8)生理(li)惰(duo)性(xing)(xing)(xing)(xing)。硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)無毒,無味,無嗅,與人體組(zu)織不(bu)粘連,具有(you)抗凝血作用(yong),對肌體組(zu)織的(de)(de)(de)(de)反應性(xing)(xing)(xing)(xing)非常少。特別適合作為(wei)醫(yi)用(yong)材料。
硅橡膠的用量
據中(zhong)國(guo)(guo)(guo)(guo)汽(qi)(qi)車(che)(che)工業(ye)(ye)協(xie)會統(tong)計,2012年(nian)(nian),汽(qi)(qi)車(che)(che)產(chan)銷分別(bie)(bie)達到(dao)1927.18萬輛和(he)1930.64萬輛,同(tong)比分別(bie)(bie)增(zeng)長(chang)(chang)4.63%和(he)4.33%,汽(qi)(qi)車(che)(che)工業(ye)(ye)硅橡膠的(de)用(yong)(yong)(yong)(yong)量(liang)約達2.0萬t。根(gen)據觀研天(tian)下的(de)新(xin)研究,增(zeng)加有(you)機(ji)(ji)硅材料在(zai)汽(qi)(qi)車(che)(che)零部(bu)(bu)件(jian)(jian)方面(mian)(mian)的(de)用(yong)(yong)(yong)(yong)量(liang),可以大幅度提(ti)高汽(qi)(qi)車(che)(che)的(de)安全性能,因此,汽(qi)(qi)車(che)(che)產(chan)量(liang)和(he)單(dan)車(che)(che)用(yong)(yong)(yong)(yong)量(liang)水(shui)平的(de)提(ti)高都將(jiang)推動(dong)汽(qi)(qi)車(che)(che)工業(ye)(ye)對硅橡膠需求的(de)增(zeng)加。國(guo)(guo)(guo)(guo)家鼓勵自主(zhu)品牌的(de)汽(qi)(qi)車(che)(che)發(fa)展(zhan),關(guan)鍵汽(qi)(qi)車(che)(che)零部(bu)(bu)件(jian)(jian)實(shi)現自主(zhu)化(hua)(hua),《2012年(nian)(nian)度黨政機(ji)(ji)關(guan)公(gong)務用(yong)(yong)(yong)(yong)車(che)(che)選用(yong)(yong)(yong)(yong)車(che)(che)型目錄(征(zheng)求意見稿)》為自主(zhu)品牌擴大在(zai)政府(fu)采購的(de)市(shi)場份額,為改變目前國(guo)(guo)(guo)(guo)內政府(fu)采購以合(he)資品牌產(chan)品為主(zhu)的(de)局(ju)面(mian)(mian)提(ti)供(gong)了保障。促進自主(zhu)品牌發(fa)展(zhan),國(guo)(guo)(guo)(guo)產(chan)汽(qi)(qi)車(che)(che)業(ye)(ye)的(de)繁榮將(jiang)為汽(qi)(qi)車(che)(che)膠的(de)應用(yong)(yong)(yong)(yong)提(ti)供(gong)有(you)力保障。預測未來3年(nian)(nian),我(wo)國(guo)(guo)(guo)(guo)室(shi)溫硫化(hua)(hua)硅橡膠在(zai)汽(qi)(qi)車(che)(che)行(xing)業(ye)(ye)將(jiang)以年(nian)(nian)均20%增(zeng)長(chang)(chang)。
此外,硅(gui)橡(xiang)(xiang)(xiang)膠(jiao)是重要(yao)的(de)(de)(de)非(fei)石(shi)油(you)基(ji)合成(cheng)(cheng)(cheng)橡(xiang)(xiang)(xiang)膠(jiao),約占非(fei)石(shi)油(you)基(ji)合成(cheng)(cheng)(cheng)橡(xiang)(xiang)(xiang)膠(jiao)消費量的(de)(de)(de)98%。但因為(wei)(wei)(wei)石(shi)油(you)價格的(de)(de)(de)大(da)幅上(shang)漲,同(tong)時我國在硅(gui)橡(xiang)(xiang)(xiang)膠(jiao)的(de)(de)(de)關(guan)鍵原料有(you)機(ji)硅(gui)單體的(de)(de)(de)生產(chan)技術(shu)(shu)方(fang)面取(qu)得突破,有(you)機(ji)硅(gui)單體的(de)(de)(de)生產(chan)技術(shu)(shu)在2005年(nian)前(qian)被幾家跨國公司(si)壟斷,但目前(qian)我國已發展(zhan)成(cheng)(cheng)(cheng)為(wei)(wei)(wei)全球(qiu)有(you)機(ji)硅(gui)單體第1大(da)國,這2個方(fang)面原因使硅(gui)橡(xiang)(xiang)(xiang)膠(jiao)的(de)(de)(de)價格從2011年(nian)起開(kai)始低(di)于石(shi)油(you)基(ji)合成(cheng)(cheng)(cheng)橡(xiang)(xiang)(xiang)膠(jiao),僅約為(wei)(wei)(wei)大(da)宗石(shi)油(you)基(ji)橡(xiang)(xiang)(xiang)膠(jiao)的(de)(de)(de)80%~90%,成(cheng)(cheng)(cheng)為(wei)(wei)(wei)廉價的(de)(de)(de)合成(cheng)(cheng)(cheng)橡(xiang)(xiang)(xiang)膠(jiao),并開(kai)始大(da)規模替代石(shi)油(you)基(ji)合成(cheng)(cheng)(cheng)橡(xiang)(xiang)(xiang)膠(jiao)。這將極(ji)大(da)拓展(zhan)有(you)機(ji)硅(gui)產(chan)業的(de)(de)(de)市(shi)場空間,同(tong)時將帶(dai)動硅(gui)油(you)、硅(gui)烷偶聯劑和硅(gui)樹脂等其(qi)他有(you)機(ji)硅(gui)產(chan)品的(de)(de)(de)消費。