
硅橡膠是(shi)指(zhi)主(zhu)鏈由(you)硅(gui)(gui)(gui)(gui)和氧原子(zi)(zi)交(jiao)替構成(cheng),硅(gui)(gui)(gui)(gui)原子(zi)(zi)上通(tong)常連有兩個(ge)有機(ji)基(ji)(ji)團的(de)(de)(de)橡(xiang)(xiang)膠(jiao)。普(pu)通(tong)的(de)(de)(de)硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)主(zhu)要由(you)含甲基(ji)(ji)和少量乙烯基(ji)(ji)的(de)(de)(de)硅(gui)(gui)(gui)(gui)氧鏈節組(zu)成(cheng)。苯基(ji)(ji)的(de)(de)(de)引(yin)(yin)入(ru)(ru)可(ke)提(ti)高(gao)(gao)(gao)(gao)硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)的(de)(de)(de)耐高(gao)(gao)(gao)(gao)、低溫(wen)性(xing)(xing)(xing)(xing)(xing)能,三氟丙基(ji)(ji)及氰基(ji)(ji)的(de)(de)(de)引(yin)(yin)入(ru)(ru)則可(ke)提(ti)高(gao)(gao)(gao)(gao)硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)的(de)(de)(de)耐溫(wen)及耐油性(xing)(xing)(xing)(xing)(xing)能。硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)耐低溫(wen)性(xing)(xing)(xing)(xing)(xing)能良(liang)好,一般在-55℃下仍能工作(zuo)。引(yin)(yin)入(ru)(ru)苯基(ji)(ji)后(hou),可(ke)達-73℃。硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)的(de)(de)(de)耐熱(re)性(xing)(xing)(xing)(xing)(xing)能也很突(tu)出(chu)(chu),在180℃下可(ke)長期工作(zuo),稍高(gao)(gao)(gao)(gao)于(yu)200℃也能承受數周(zhou)或更(geng)長時間(jian)仍有彈性(xing)(xing)(xing)(xing)(xing),瞬時可(ke)耐300℃以上的(de)(de)(de)高(gao)(gao)(gao)(gao)溫(wen)。硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)的(de)(de)(de)透氣(qi)性(xing)(xing)(xing)(xing)(xing)好,氧氣(qi)透過率在合成(cheng)聚合物中(zhong)是(shi)較(jiao)高(gao)(gao)(gao)(gao)的(de)(de)(de)。此外(wai),硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)還具有生理(li)惰(duo)性(xing)(xing)(xing)(xing)(xing)、不會導致凝血的(de)(de)(de)突(tu)出(chu)(chu)特性(xing)(xing)(xing)(xing)(xing),因此在醫用領(ling)域(yu)應用廣泛。
主要品種
硅(gui)(gui)橡(xiang)膠(jiao)(jiao)分(fen)(fen)類的方法很多(duo),通(tong)常按固(gu)化(hua)前(qian)的形(xing)態分(fen)(fen)為(wei)(wei)(wei)(wei)固(gu)體硅(gui)(gui)橡(xiang)膠(jiao)(jiao)和液體硅(gui)(gui)橡(xiang)膠(jiao)(jiao);按硫化(hua)溫(wen)(wen)度分(fen)(fen)為(wei)(wei)(wei)(wei)室溫(wen)(wen)硫化(hua)硅(gui)(gui)橡(xiang)膠(jiao)(jiao),高溫(wen)(wen)硫化(hua)硅(gui)(gui)橡(xiang)膠(jiao)(jiao);按所(suo)用(yong)(yong)(yong)單體的不同,可分(fen)(fen)為(wei)(wei)(wei)(wei)甲基(ji)乙烯(xi)基(ji)硅(gui)(gui)橡(xiang)膠(jiao)(jiao),甲基(ji)苯(ben)基(ji)乙烯(xi)基(ji)硅(gui)(gui)橡(xiang)膠(jiao)(jiao)、氟硅(gui)(gui),腈硅(gui)(gui)橡(xiang)膠(jiao)(jiao)等;按性能和用(yong)(yong)(yong)途(tu)的不同又可分(fen)(fen)為(wei)(wei)(wei)(wei)通(tong)用(yong)(yong)(yong)型(xing)、超(chao)耐(nai)(nai)低(di)溫(wen)(wen)型(xing)、超(chao)耐(nai)(nai)高溫(wen)(wen)型(xing)、高強力型(xing)、耐(nai)(nai)油型(xing)、醫用(yong)(yong)(yong)型(xing)等等。
發(fa)展史
硅(gui)橡(xiang)膠(jiao)(jiao)(jiao)早期是由美國(guo)(guo)以三氯化(hua)(hua)鐵(tie)為(wei)催化(hua)(hua)劑合成(cheng)(cheng)的。1945年(nian),硅(gui)橡(xiang)膠(jiao)(jiao)(jiao)產(chan)品問世(shi)。1948年(nian),采用高比表面積的氣相法白炭黑補強的硅(gui)橡(xiang)膠(jiao)(jiao)(jiao)研制成(cheng)(cheng)功,使硅(gui)橡(xiang)膠(jiao)(jiao)(jiao)的性能躍升到(dao)實用階段,奠(dian)定了現代硅(gui)橡(xiang)膠(jiao)(jiao)(jiao)生產(chan)技術(shu)的基(ji)(ji)礎。從(cong)二(er)甲基(ji)(ji)二(er)氯硅(gui)烷合成(cheng)(cheng)開始生產(chan)硅(gui)橡(xiang)膠(jiao)(jiao)(jiao)的國(guo)(guo)家有(you)美國(guo)(guo)。俄羅(luo)斯、德(de)國(guo)(guo)、日(ri)本、韓國(guo)(guo)和中國(guo)(guo)等(deng)。中國(guo)(guo)硅(gui)橡(xiang)膠(jiao)(jiao)(jiao)的工業化(hua)(hua)研究(jiu)始于(yu)1957年(nian),多家研究(jiu)所(suo)和企(qi)業陸(lu)續開發出各種硅(gui)橡(xiang)膠(jiao)(jiao)(jiao)。到(dao)2003年(nian)底,中國(guo)(guo)硅(gui)橡(xiang)膠(jiao)(jiao)(jiao)生產(chan)能力(li)為(wei)135千噸(dun),其中高溫膠(jiao)(jiao)(jiao)100千噸(dun)。
高(gao)溫(wen)硫化硅(gui)橡膠
高(gao)溫(wen)硫(liu)化(hua)(hua)(hua)硅橡膠(jiao)(jiao)(jiao)是(shi)指(zhi)聚硅氧烷(wan)變成(cheng)(cheng)(cheng)彈性體(ti)的(de)過(guo)程是(shi)經過(guo)高(gao)溫(wen)(110-170℃)硫(liu)化(hua)(hua)(hua)成(cheng)(cheng)(cheng)型的(de)。它(ta)主要(yao)以高(gao)分子量的(de)聚甲基乙烯基硅氧烷(wan)為生(sheng)膠(jiao)(jiao)(jiao),混(hun)入補強(qiang)(qiang)填料(liao)、硫(liu)化(hua)(hua)(hua)劑等(deng),在加(jia)熱加(jia)壓下硫(liu)化(hua)(hua)(hua)成(cheng)(cheng)(cheng)彈性體(ti)。硅橡膠(jiao)(jiao)(jiao)的(de)補強(qiang)(qiang)主要(yao)是(shi)各(ge)(ge)(ge)種類型的(de)白炭黑(hei),可使硫(liu)化(hua)(hua)(hua)膠(jiao)(jiao)(jiao)的(de)強(qiang)(qiang)度(du)增加(jia)數十倍。有時為了(le)降低成(cheng)(cheng)(cheng)本或改善膠(jiao)(jiao)(jiao)料(liao)性能及賦予硫(liu)化(hua)(hua)(hua)膠(jiao)(jiao)(jiao)各(ge)(ge)(ge)種特(te)殊的(de)性能,也加(jia)入相應的(de)各(ge)(ge)(ge)種添加(jia)劑。硫(liu)化(hua)(hua)(hua)劑是(shi)各(ge)(ge)(ge)種有機過(guo)氧化(hua)(hua)(hua)物或加(jia)成(cheng)(cheng)(cheng)反應催化(hua)(hua)(hua)劑。
加工成型方(fang)法如圖所示。一次硫(liu)(liu)化(hua)的目(mu)的是進行(xing)(xing)高分子鏈的交(jiao)聯反應;二次硫(liu)(liu)化(hua)的目(mu)的是進行(xing)(xing)補充(chong)交(jiao)聯、驅除硫(liu)(liu)化(hua)劑分解產物(wu)和其他揮發性(xing)化(hua)合物(wu)以穩定硫(liu)(liu)化(hua)膠的各項性(xing)能。常用的設備有開放(fang)式煉(lian)膠機、捏(nie)合機及(ji)真空密(mi)煉(lian)機。
主(zhu)要性(xing)能
(1)高溫(wen)(wen)(wen)(wen)性(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)。硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)顯著(zhu)的(de)(de)(de)特征(zheng)是高溫(wen)(wen)(wen)(wen)穩定(ding)性(xing)(xing)(xing)(xing)(xing),雖然(ran)常(chang)溫(wen)(wen)(wen)(wen)下(xia)(xia)硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)的(de)(de)(de)強(qiang)度僅是天然(ran)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)或某些合成(cheng)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)的(de)(de)(de)一(yi)半,但在200℃以(yi)上的(de)(de)(de)高溫(wen)(wen)(wen)(wen)環(huan)境下(xia)(xia),硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)仍能(neng)(neng)(neng)保持一(yi)定(ding)的(de)(de)(de)柔韌性(xing)(xing)(xing)(xing)(xing)、回彈性(xing)(xing)(xing)(xing)(xing)和表面硬度,且力(li)學性(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)無明(ming)(ming)顯變化。(2)低(di)溫(wen)(wen)(wen)(wen)性(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)的(de)(de)(de)玻璃化溫(wen)(wen)(wen)(wen)度一(yi)般(ban)為-70~-50℃,特殊配方可達(da)-100℃,表明(ming)(ming)其(qi)低(di)溫(wen)(wen)(wen)(wen)性(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)優異(yi)。這對航(hang)空、宇航(hang)工業(ye)的(de)(de)(de)意義重大(da)。(3)耐(nai)候(hou)性(xing)(xing)(xing)(xing)(xing)硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)中Si-O-Si鍵對氧、臭氧及紫外線等十分穩定(ding),在不(bu)(bu)加任何(he)添(tian)加劑(ji)的(de)(de)(de)情況下(xia)(xia),就(jiu)具(ju)有(you)(you)優良的(de)(de)(de)耐(nai)候(hou)性(xing)(xing)(xing)(xing)(xing)。(4)電(dian)氣(qi)性(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)。硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)具(ju)有(you)(you)優異(yi)的(de)(de)(de)絕(jue)緣性(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng),耐(nai)電(dian)暈性(xing)(xing)(xing)(xing)(xing)和耐(nai)電(dian)弧性(xing)(xing)(xing)(xing)(xing)也非(fei)常(chang)好。(5)物理機械(xie)性(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)。硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)常(chang)溫(wen)(wen)(wen)(wen)下(xia)(xia)的(de)(de)(de)物理機械(xie)性(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)比通(tong)用橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)差,但在150℃的(de)(de)(de)高溫(wen)(wen)(wen)(wen)和-50℃的(de)(de)(de)低(di)溫(wen)(wen)(wen)(wen)下(xia)(xia),其(qi)物理機械(xie)性(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)優于通(tong)用橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)。(6)耐(nai)油及化學試(shi)劑(ji)性(xing)(xing)(xing)(xing)(xing)。普通(tong)硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)具(ju)有(you)(you)中等的(de)(de)(de)耐(nai)油、耐(nai)溶劑(ji)性(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)。(7)氣(qi)體(ti)(ti)透(tou)過性(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)。室溫(wen)(wen)(wen)(wen)下(xia)(xia)硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)對空氣(qi)、氮(dan)、氧、二氧化碳等氣(qi)體(ti)(ti)的(de)(de)(de)透(tou)氣(qi)性(xing)(xing)(xing)(xing)(xing)比天然(ran)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)高出30-50倍。(8)生理惰(duo)性(xing)(xing)(xing)(xing)(xing)。硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)無毒,無味,無嗅,與人體(ti)(ti)組(zu)織(zhi)不(bu)(bu)粘連(lian),具(ju)有(you)(you)抗凝血作(zuo)(zuo)用,對肌(ji)體(ti)(ti)組(zu)織(zhi)的(de)(de)(de)反應性(xing)(xing)(xing)(xing)(xing)非(fei)常(chang)少。特別適合作(zuo)(zuo)為醫用材料(liao)。
硅(gui)橡(xiang)膠的用量
據(ju)(ju)中(zhong)國(guo)(guo)汽(qi)(qi)(qi)(qi)車(che)(che)(che)工(gong)業(ye)協會統計,2012年(nian),汽(qi)(qi)(qi)(qi)車(che)(che)(che)產(chan)銷(xiao)分(fen)別達(da)到(dao)1927.18萬(wan)(wan)輛和1930.64萬(wan)(wan)輛,同比分(fen)別增(zeng)長4.63%和4.33%,汽(qi)(qi)(qi)(qi)車(che)(che)(che)工(gong)業(ye)硅(gui)橡膠(jiao)的(de)(de)(de)(de)用(yong)量約達(da)2.0萬(wan)(wan)t。根據(ju)(ju)觀研天下(xia)的(de)(de)(de)(de)新研究(jiu),增(zeng)加有機(ji)硅(gui)材料在汽(qi)(qi)(qi)(qi)車(che)(che)(che)零部件方面(mian)的(de)(de)(de)(de)用(yong)量,可以大(da)幅(fu)度提高汽(qi)(qi)(qi)(qi)車(che)(che)(che)的(de)(de)(de)(de)安全性(xing)能,因此,汽(qi)(qi)(qi)(qi)車(che)(che)(che)產(chan)量和單車(che)(che)(che)用(yong)量水平的(de)(de)(de)(de)提高都將推(tui)動汽(qi)(qi)(qi)(qi)車(che)(che)(che)工(gong)業(ye)對(dui)硅(gui)橡膠(jiao)需(xu)求的(de)(de)(de)(de)增(zeng)加。國(guo)(guo)家鼓勵自主品(pin)牌的(de)(de)(de)(de)汽(qi)(qi)(qi)(qi)車(che)(che)(che)發(fa)展,關(guan)鍵汽(qi)(qi)(qi)(qi)車(che)(che)(che)零部件實現自主化,《2012年(nian)度黨政(zheng)機(ji)關(guan)公務(wu)用(yong)車(che)(che)(che)選用(yong)車(che)(che)(che)型目(mu)錄(征求意見稿)》為(wei)(wei)(wei)自主品(pin)牌擴大(da)在政(zheng)府(fu)采(cai)購(gou)的(de)(de)(de)(de)市場份額,為(wei)(wei)(wei)改變目(mu)前國(guo)(guo)內政(zheng)府(fu)采(cai)購(gou)以合資品(pin)牌產(chan)品(pin)為(wei)(wei)(wei)主的(de)(de)(de)(de)局面(mian)提供(gong)了保障(zhang)。促進自主品(pin)牌發(fa)展,國(guo)(guo)產(chan)汽(qi)(qi)(qi)(qi)車(che)(che)(che)業(ye)的(de)(de)(de)(de)繁榮將為(wei)(wei)(wei)汽(qi)(qi)(qi)(qi)車(che)(che)(che)膠(jiao)的(de)(de)(de)(de)應用(yong)提供(gong)有力保障(zhang)。預測未來3年(nian),我(wo)國(guo)(guo)室溫硫化硅(gui)橡膠(jiao)在汽(qi)(qi)(qi)(qi)車(che)(che)(che)行業(ye)將以年(nian)均20%增(zeng)長。
此外(wai),硅(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)是重要(yao)的非石(shi)油(you)基合成(cheng)(cheng)(cheng)橡(xiang)(xiang)(xiang)膠(jiao)(jiao),約占非石(shi)油(you)基合成(cheng)(cheng)(cheng)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)消費量的98%。但(dan)因為(wei)石(shi)油(you)價格的大幅上漲,同時我國(guo)(guo)在硅(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)的關鍵(jian)原料有機硅(gui)單(dan)體(ti)(ti)的生產(chan)技術(shu)方(fang)面(mian)取得(de)突破(po),有機硅(gui)單(dan)體(ti)(ti)的生產(chan)技術(shu)在2005年前被(bei)幾家(jia)跨國(guo)(guo)公司壟斷,但(dan)目前我國(guo)(guo)已發展成(cheng)(cheng)(cheng)為(wei)全(quan)球有機硅(gui)單(dan)體(ti)(ti)第1大國(guo)(guo),這2個(ge)方(fang)面(mian)原因使(shi)硅(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)的價格從2011年起開始低于石(shi)油(you)基合成(cheng)(cheng)(cheng)橡(xiang)(xiang)(xiang)膠(jiao)(jiao),僅約為(wei)大宗石(shi)油(you)基橡(xiang)(xiang)(xiang)膠(jiao)(jiao)的80%~90%,成(cheng)(cheng)(cheng)為(wei)廉價的合成(cheng)(cheng)(cheng)橡(xiang)(xiang)(xiang)膠(jiao)(jiao),并開始大規模替代石(shi)油(you)基合成(cheng)(cheng)(cheng)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)。這將極大拓展有機硅(gui)產(chan)業(ye)的市場空間,同時將帶動(dong)硅(gui)油(you)、硅(gui)烷偶(ou)聯劑和硅(gui)樹(shu)脂等其他有機硅(gui)產(chan)品(pin)的消費。