
硅橡膠是(shi)指主鏈由硅(gui)和氧(yang)原子交替構成(cheng),硅(gui)原子上通(tong)(tong)常(chang)連有兩(liang)個(ge)有機基(ji)(ji)團的(de)(de)(de)橡膠(jiao)。普通(tong)(tong)的(de)(de)(de)硅(gui)橡膠(jiao)主要由含甲(jia)基(ji)(ji)和少量(liang)乙烯基(ji)(ji)的(de)(de)(de)硅(gui)氧(yang)鏈節(jie)組(zu)成(cheng)。苯(ben)基(ji)(ji)的(de)(de)(de)引入(ru)可(ke)提高(gao)(gao)硅(gui)橡膠(jiao)的(de)(de)(de)耐高(gao)(gao)、低(di)溫(wen)性(xing)(xing)(xing)(xing)能(neng),三氟(fu)丙基(ji)(ji)及氰基(ji)(ji)的(de)(de)(de)引入(ru)則可(ke)提高(gao)(gao)硅(gui)橡膠(jiao)的(de)(de)(de)耐溫(wen)及耐油性(xing)(xing)(xing)(xing)能(neng)。硅(gui)橡膠(jiao)耐低(di)溫(wen)性(xing)(xing)(xing)(xing)能(neng)良好,一般在-55℃下(xia)仍(reng)能(neng)工(gong)作(zuo)。引入(ru)苯(ben)基(ji)(ji)后,可(ke)達-73℃。硅(gui)橡膠(jiao)的(de)(de)(de)耐熱性(xing)(xing)(xing)(xing)能(neng)也(ye)很突(tu)出,在180℃下(xia)可(ke)長(chang)期(qi)工(gong)作(zuo),稍高(gao)(gao)于200℃也(ye)能(neng)承受數周(zhou)或更長(chang)時間仍(reng)有彈性(xing)(xing)(xing)(xing),瞬(shun)時可(ke)耐300℃以上的(de)(de)(de)高(gao)(gao)溫(wen)。硅(gui)橡膠(jiao)的(de)(de)(de)透氣性(xing)(xing)(xing)(xing)好,氧(yang)氣透過率在合成(cheng)聚合物中是(shi)較高(gao)(gao)的(de)(de)(de)。此(ci)(ci)外,硅(gui)橡膠(jiao)還具有生理惰性(xing)(xing)(xing)(xing)、不(bu)會導致(zhi)凝血的(de)(de)(de)突(tu)出特性(xing)(xing)(xing)(xing),因此(ci)(ci)在醫用領域應用廣泛(fan)。
主要品種
硅(gui)(gui)橡(xiang)(xiang)(xiang)膠分(fen)(fen)類(lei)的方(fang)法很多,通(tong)常按固化(hua)前(qian)的形態(tai)分(fen)(fen)為(wei)(wei)固體(ti)硅(gui)(gui)橡(xiang)(xiang)(xiang)膠和液體(ti)硅(gui)(gui)橡(xiang)(xiang)(xiang)膠;按硫化(hua)溫度(du)分(fen)(fen)為(wei)(wei)室溫硫化(hua)硅(gui)(gui)橡(xiang)(xiang)(xiang)膠,高溫硫化(hua)硅(gui)(gui)橡(xiang)(xiang)(xiang)膠;按所(suo)用單體(ti)的不同,可分(fen)(fen)為(wei)(wei)甲(jia)基乙烯基硅(gui)(gui)橡(xiang)(xiang)(xiang)膠,甲(jia)基苯基乙烯基硅(gui)(gui)橡(xiang)(xiang)(xiang)膠、氟(fu)硅(gui)(gui),腈(jing)硅(gui)(gui)橡(xiang)(xiang)(xiang)膠等(deng);按性能和用途(tu)的不同又可分(fen)(fen)為(wei)(wei)通(tong)用型(xing)(xing)、超耐(nai)低溫型(xing)(xing)、超耐(nai)高溫型(xing)(xing)、高強力型(xing)(xing)、耐(nai)油型(xing)(xing)、醫用型(xing)(xing)等(deng)等(deng)。
發展史
硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)早期是(shi)由(you)美國(guo)(guo)(guo)(guo)以三氯化鐵(tie)為(wei)(wei)催化劑(ji)合成(cheng)的(de)。1945年(nian),硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)產(chan)品(pin)問世。1948年(nian),采(cai)用(yong)(yong)高比表面積(ji)的(de)氣相(xiang)法白炭(tan)黑(hei)補強的(de)硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)研制成(cheng)功,使硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)的(de)性能(neng)(neng)躍(yue)升到實(shi)用(yong)(yong)階段,奠定了現代(dai)硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)生(sheng)(sheng)產(chan)技術的(de)基(ji)礎。從二(er)甲基(ji)二(er)氯硅(gui)(gui)烷(wan)合成(cheng)開始生(sheng)(sheng)產(chan)硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)的(de)國(guo)(guo)(guo)(guo)家(jia)有美國(guo)(guo)(guo)(guo)。俄羅(luo)斯(si)、德國(guo)(guo)(guo)(guo)、日本、韓國(guo)(guo)(guo)(guo)和(he)中國(guo)(guo)(guo)(guo)等。中國(guo)(guo)(guo)(guo)硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)的(de)工業化研究始于(yu)1957年(nian),多家(jia)研究所和(he)企業陸續開發出(chu)各種(zhong)硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)。到2003年(nian)底,中國(guo)(guo)(guo)(guo)硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)生(sheng)(sheng)產(chan)能(neng)(neng)力(li)為(wei)(wei)135千噸(dun),其中高溫膠(jiao)(jiao)100千噸(dun)。
高溫硫化硅橡膠
高溫硫(liu)(liu)(liu)(liu)化(hua)硅(gui)橡膠(jiao)(jiao)是(shi)指(zhi)聚硅(gui)氧(yang)(yang)烷(wan)(wan)變成(cheng)彈(dan)性(xing)(xing)體的過(guo)程是(shi)經過(guo)高溫(110-170℃)硫(liu)(liu)(liu)(liu)化(hua)成(cheng)型的。它主(zhu)要以高分子量的聚甲(jia)基乙烯(xi)基硅(gui)氧(yang)(yang)烷(wan)(wan)為生膠(jiao)(jiao),混入補強填料(liao)、硫(liu)(liu)(liu)(liu)化(hua)劑等(deng),在加(jia)熱加(jia)壓下硫(liu)(liu)(liu)(liu)化(hua)成(cheng)彈(dan)性(xing)(xing)體。硅(gui)橡膠(jiao)(jiao)的補強主(zhu)要是(shi)各(ge)種(zhong)(zhong)類型的白炭黑,可使硫(liu)(liu)(liu)(liu)化(hua)膠(jiao)(jiao)的強度增(zeng)加(jia)數十倍。有時(shi)為了降低(di)成(cheng)本或(huo)改善膠(jiao)(jiao)料(liao)性(xing)(xing)能及賦予硫(liu)(liu)(liu)(liu)化(hua)膠(jiao)(jiao)各(ge)種(zhong)(zhong)特殊的性(xing)(xing)能,也加(jia)入相應(ying)的各(ge)種(zhong)(zhong)添加(jia)劑。硫(liu)(liu)(liu)(liu)化(hua)劑是(shi)各(ge)種(zhong)(zhong)有機過(guo)氧(yang)(yang)化(hua)物或(huo)加(jia)成(cheng)反應(ying)催化(hua)劑。
加工成型方法如圖所(suo)示。一次(ci)(ci)硫化(hua)的目的是(shi)進行高分子鏈的交(jiao)聯反應;二次(ci)(ci)硫化(hua)的目的是(shi)進行補(bu)充交(jiao)聯、驅除硫化(hua)劑分解產物(wu)和其(qi)他(ta)揮發(fa)性化(hua)合(he)物(wu)以穩定硫化(hua)膠的各項(xiang)性能(neng)。常用的設備有開(kai)放式煉膠機(ji)、捏合(he)機(ji)及真空密(mi)煉機(ji)。
主要性能
(1)高溫(wen)(wen)(wen)(wen)(wen)性(xing)(xing)(xing)(xing)能(neng)(neng)(neng)。硅(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)顯著的(de)(de)(de)特征(zheng)是(shi)高溫(wen)(wen)(wen)(wen)(wen)穩定性(xing)(xing)(xing)(xing),雖然常(chang)(chang)溫(wen)(wen)(wen)(wen)(wen)下硅(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)的(de)(de)(de)強度(du)(du)僅是(shi)天然橡(xiang)(xiang)膠(jiao)或(huo)某些(xie)合成橡(xiang)(xiang)膠(jiao)的(de)(de)(de)一半,但在200℃以上的(de)(de)(de)高溫(wen)(wen)(wen)(wen)(wen)環境下,硅(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)仍能(neng)(neng)(neng)保持一定的(de)(de)(de)柔韌性(xing)(xing)(xing)(xing)、回彈性(xing)(xing)(xing)(xing)和表面硬度(du)(du),且(qie)力學性(xing)(xing)(xing)(xing)能(neng)(neng)(neng)無明(ming)顯變化。(2)低溫(wen)(wen)(wen)(wen)(wen)性(xing)(xing)(xing)(xing)能(neng)(neng)(neng)硅(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)的(de)(de)(de)玻(bo)璃化溫(wen)(wen)(wen)(wen)(wen)度(du)(du)一般為-70~-50℃,特殊配方可達-100℃,表明(ming)其低溫(wen)(wen)(wen)(wen)(wen)性(xing)(xing)(xing)(xing)能(neng)(neng)(neng)優異。這對(dui)航(hang)空(kong)、宇航(hang)工(gong)業的(de)(de)(de)意義重大(da)。(3)耐(nai)(nai)候性(xing)(xing)(xing)(xing)硅(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)中Si-O-Si鍵對(dui)氧、臭(chou)氧及紫外線等(deng)十(shi)分穩定,在不加(jia)任何添加(jia)劑的(de)(de)(de)情況下,就具(ju)有優良(liang)的(de)(de)(de)耐(nai)(nai)候性(xing)(xing)(xing)(xing)。(4)電(dian)氣(qi)性(xing)(xing)(xing)(xing)能(neng)(neng)(neng)。硅(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)具(ju)有優異的(de)(de)(de)絕緣性(xing)(xing)(xing)(xing)能(neng)(neng)(neng),耐(nai)(nai)電(dian)暈性(xing)(xing)(xing)(xing)和耐(nai)(nai)電(dian)弧性(xing)(xing)(xing)(xing)也非(fei)(fei)常(chang)(chang)好(hao)。(5)物(wu)理機械性(xing)(xing)(xing)(xing)能(neng)(neng)(neng)。硅(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)常(chang)(chang)溫(wen)(wen)(wen)(wen)(wen)下的(de)(de)(de)物(wu)理機械性(xing)(xing)(xing)(xing)能(neng)(neng)(neng)比通用橡(xiang)(xiang)膠(jiao)差,但在150℃的(de)(de)(de)高溫(wen)(wen)(wen)(wen)(wen)和-50℃的(de)(de)(de)低溫(wen)(wen)(wen)(wen)(wen)下,其物(wu)理機械性(xing)(xing)(xing)(xing)能(neng)(neng)(neng)優于通用橡(xiang)(xiang)膠(jiao)。(6)耐(nai)(nai)油及化學試劑性(xing)(xing)(xing)(xing)。普通硅(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)具(ju)有中等(deng)的(de)(de)(de)耐(nai)(nai)油、耐(nai)(nai)溶(rong)劑性(xing)(xing)(xing)(xing)能(neng)(neng)(neng)。(7)氣(qi)體(ti)透過性(xing)(xing)(xing)(xing)能(neng)(neng)(neng)。室溫(wen)(wen)(wen)(wen)(wen)下硅(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)對(dui)空(kong)氣(qi)、氮、氧、二(er)氧化碳等(deng)氣(qi)體(ti)的(de)(de)(de)透氣(qi)性(xing)(xing)(xing)(xing)比天然橡(xiang)(xiang)膠(jiao)高出30-50倍。(8)生(sheng)理惰(duo)性(xing)(xing)(xing)(xing)。硅(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)無毒,無味(wei),無嗅,與人體(ti)組(zu)(zu)織(zhi)不粘連,具(ju)有抗凝(ning)血作(zuo)用,對(dui)肌體(ti)組(zu)(zu)織(zhi)的(de)(de)(de)反應性(xing)(xing)(xing)(xing)非(fei)(fei)常(chang)(chang)少。特別適合作(zuo)為醫用材料(liao)。
硅橡膠的用量
據中國汽(qi)(qi)車(che)工(gong)(gong)業(ye)協會統計,2012年(nian),汽(qi)(qi)車(che)產(chan)(chan)銷(xiao)分(fen)別(bie)達到(dao)1927.18萬(wan)輛和1930.64萬(wan)輛,同比分(fen)別(bie)增(zeng)(zeng)長4.63%和4.33%,汽(qi)(qi)車(che)工(gong)(gong)業(ye)硅橡膠的(de)(de)(de)用(yong)量約達2.0萬(wan)t。根(gen)據觀研天下的(de)(de)(de)新研究(jiu),增(zeng)(zeng)加有(you)機(ji)硅材料在汽(qi)(qi)車(che)零(ling)部(bu)件方面的(de)(de)(de)用(yong)量,可以(yi)大(da)幅度(du)提(ti)高(gao)汽(qi)(qi)車(che)的(de)(de)(de)安全性(xing)能,因此,汽(qi)(qi)車(che)產(chan)(chan)量和單車(che)用(yong)量水平的(de)(de)(de)提(ti)高(gao)都(dou)將推(tui)動(dong)汽(qi)(qi)車(che)工(gong)(gong)業(ye)對硅橡膠需求的(de)(de)(de)增(zeng)(zeng)加。國家鼓(gu)勵(li)自主(zhu)(zhu)品(pin)牌(pai)(pai)的(de)(de)(de)汽(qi)(qi)車(che)發展(zhan),關(guan)鍵汽(qi)(qi)車(che)零(ling)部(bu)件實(shi)現自主(zhu)(zhu)化,《2012年(nian)度(du)黨政機(ji)關(guan)公務用(yong)車(che)選用(yong)車(che)型目錄(lu)(征求意(yi)見稿)》為(wei)自主(zhu)(zhu)品(pin)牌(pai)(pai)擴(kuo)大(da)在政府(fu)(fu)采購的(de)(de)(de)市場份(fen)額(e),為(wei)改變目前國內政府(fu)(fu)采購以(yi)合資品(pin)牌(pai)(pai)產(chan)(chan)品(pin)為(wei)主(zhu)(zhu)的(de)(de)(de)局面提(ti)供(gong)了保障(zhang)。促(cu)進自主(zhu)(zhu)品(pin)牌(pai)(pai)發展(zhan),國產(chan)(chan)汽(qi)(qi)車(che)業(ye)的(de)(de)(de)繁(fan)榮(rong)將為(wei)汽(qi)(qi)車(che)膠的(de)(de)(de)應用(yong)提(ti)供(gong)有(you)力保障(zhang)。預測未來3年(nian),我國室溫硫化硅橡膠在汽(qi)(qi)車(che)行業(ye)將以(yi)年(nian)均20%增(zeng)(zeng)長。
此外(wai),硅(gui)(gui)(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)是重(zhong)要的(de)(de)(de)非(fei)石(shi)(shi)(shi)(shi)(shi)油基合(he)(he)成(cheng)(cheng)橡(xiang)(xiang)(xiang)膠(jiao),約占(zhan)非(fei)石(shi)(shi)(shi)(shi)(shi)油基合(he)(he)成(cheng)(cheng)橡(xiang)(xiang)(xiang)膠(jiao)消費量的(de)(de)(de)98%。但(dan)因為(wei)(wei)石(shi)(shi)(shi)(shi)(shi)油價(jia)格的(de)(de)(de)大(da)幅上(shang)漲(zhang),同(tong)時我(wo)國(guo)在硅(gui)(gui)(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)的(de)(de)(de)關(guan)鍵原(yuan)料(liao)有(you)(you)機硅(gui)(gui)(gui)(gui)(gui)(gui)單體的(de)(de)(de)生(sheng)產技術(shu)方(fang)面取得突破(po),有(you)(you)機硅(gui)(gui)(gui)(gui)(gui)(gui)單體的(de)(de)(de)生(sheng)產技術(shu)在2005年前(qian)被幾家跨(kua)國(guo)公司壟斷,但(dan)目前(qian)我(wo)國(guo)已(yi)發展成(cheng)(cheng)為(wei)(wei)全球有(you)(you)機硅(gui)(gui)(gui)(gui)(gui)(gui)單體第(di)1大(da)國(guo),這2個方(fang)面原(yuan)因使硅(gui)(gui)(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)的(de)(de)(de)價(jia)格從2011年起開始(shi)低(di)于(yu)石(shi)(shi)(shi)(shi)(shi)油基合(he)(he)成(cheng)(cheng)橡(xiang)(xiang)(xiang)膠(jiao),僅(jin)約為(wei)(wei)大(da)宗(zong)石(shi)(shi)(shi)(shi)(shi)油基橡(xiang)(xiang)(xiang)膠(jiao)的(de)(de)(de)80%~90%,成(cheng)(cheng)為(wei)(wei)廉價(jia)的(de)(de)(de)合(he)(he)成(cheng)(cheng)橡(xiang)(xiang)(xiang)膠(jiao),并開始(shi)大(da)規模替代石(shi)(shi)(shi)(shi)(shi)油基合(he)(he)成(cheng)(cheng)橡(xiang)(xiang)(xiang)膠(jiao)。這將極大(da)拓展有(you)(you)機硅(gui)(gui)(gui)(gui)(gui)(gui)產業(ye)的(de)(de)(de)市(shi)場空間,同(tong)時將帶動(dong)硅(gui)(gui)(gui)(gui)(gui)(gui)油、硅(gui)(gui)(gui)(gui)(gui)(gui)烷偶聯劑和硅(gui)(gui)(gui)(gui)(gui)(gui)樹(shu)脂等(deng)其(qi)他有(you)(you)機硅(gui)(gui)(gui)(gui)(gui)(gui)產品的(de)(de)(de)消費。