硅橡膠是指主鏈由硅(gui)和氧(yang)原子交(jiao)替構成,硅(gui)原子上通(tong)(tong)常連有兩個有機基(ji)(ji)團的(de)(de)(de)橡(xiang)膠(jiao)(jiao)(jiao)。普通(tong)(tong)的(de)(de)(de)硅(gui)橡(xiang)膠(jiao)(jiao)(jiao)主要由含(han)甲(jia)基(ji)(ji)和少量乙烯基(ji)(ji)的(de)(de)(de)硅(gui)氧(yang)鏈節組成。苯基(ji)(ji)的(de)(de)(de)引(yin)入可提高(gao)硅(gui)橡(xiang)膠(jiao)(jiao)(jiao)的(de)(de)(de)耐(nai)(nai)高(gao)、低(di)溫(wen)性(xing)能(neng),三氟丙(bing)基(ji)(ji)及(ji)氰(qing)基(ji)(ji)的(de)(de)(de)引(yin)入則可提高(gao)硅(gui)橡(xiang)膠(jiao)(jiao)(jiao)的(de)(de)(de)耐(nai)(nai)溫(wen)及(ji)耐(nai)(nai)油性(xing)能(neng)。硅(gui)橡(xiang)膠(jiao)(jiao)(jiao)耐(nai)(nai)低(di)溫(wen)性(xing)能(neng)良好,一(yi)般在(zai)-55℃下(xia)仍能(neng)工(gong)作。引(yin)入苯基(ji)(ji)后(hou),可達(da)-73℃。硅(gui)橡(xiang)膠(jiao)(jiao)(jiao)的(de)(de)(de)耐(nai)(nai)熱性(xing)能(neng)也很突出,在(zai)180℃下(xia)可長期工(gong)作,稍(shao)高(gao)于200℃也能(neng)承受數周或更(geng)長時間仍有彈性(xing),瞬(shun)時可耐(nai)(nai)300℃以上的(de)(de)(de)高(gao)溫(wen)。硅(gui)橡(xiang)膠(jiao)(jiao)(jiao)的(de)(de)(de)透氣性(xing)好,氧(yang)氣透過率在(zai)合成聚合物中是較高(gao)的(de)(de)(de)。此(ci)外,硅(gui)橡(xiang)膠(jiao)(jiao)(jiao)還具有生(sheng)理惰性(xing)、不會導致凝血的(de)(de)(de)突出特性(xing),因(yin)此(ci)在(zai)醫用領域應用廣泛。
主要品種
硅橡(xiang)(xiang)膠(jiao)(jiao)(jiao)分(fen)類(lei)的(de)方法很多,通(tong)常(chang)按(an)固化前的(de)形態分(fen)為(wei)固體硅橡(xiang)(xiang)膠(jiao)(jiao)(jiao)和液體硅橡(xiang)(xiang)膠(jiao)(jiao)(jiao);按(an)硫(liu)化溫度分(fen)為(wei)室溫硫(liu)化硅橡(xiang)(xiang)膠(jiao)(jiao)(jiao),高溫硫(liu)化硅橡(xiang)(xiang)膠(jiao)(jiao)(jiao);按(an)所用(yong)(yong)單體的(de)不同,可分(fen)為(wei)甲(jia)基乙烯(xi)基硅橡(xiang)(xiang)膠(jiao)(jiao)(jiao),甲(jia)基苯(ben)基乙烯(xi)基硅橡(xiang)(xiang)膠(jiao)(jiao)(jiao)、氟硅,腈硅橡(xiang)(xiang)膠(jiao)(jiao)(jiao)等;按(an)性能和用(yong)(yong)途(tu)的(de)不同又可分(fen)為(wei)通(tong)用(yong)(yong)型(xing)、超耐低溫型(xing)、超耐高溫型(xing)、高強力型(xing)、耐油型(xing)、醫用(yong)(yong)型(xing)等等。
發展史
硅(gui)(gui)橡(xiang)膠(jiao)(jiao)早(zao)期是由美(mei)國(guo)(guo)(guo)(guo)(guo)以三氯(lv)化鐵為(wei)催化劑合成(cheng)的(de)。1945年,硅(gui)(gui)橡(xiang)膠(jiao)(jiao)產品(pin)問世。1948年,采用高(gao)比表面積的(de)氣相法白炭黑補強(qiang)的(de)硅(gui)(gui)橡(xiang)膠(jiao)(jiao)研制成(cheng)功,使硅(gui)(gui)橡(xiang)膠(jiao)(jiao)的(de)性(xing)能(neng)躍升(sheng)到實用階(jie)段,奠定了現代硅(gui)(gui)橡(xiang)膠(jiao)(jiao)生產技術(shu)的(de)基礎。從二(er)甲基二(er)氯(lv)硅(gui)(gui)烷合成(cheng)開(kai)始生產硅(gui)(gui)橡(xiang)膠(jiao)(jiao)的(de)國(guo)(guo)(guo)(guo)(guo)家有美(mei)國(guo)(guo)(guo)(guo)(guo)。俄羅斯、德(de)國(guo)(guo)(guo)(guo)(guo)、日(ri)本(ben)、韓國(guo)(guo)(guo)(guo)(guo)和中(zhong)國(guo)(guo)(guo)(guo)(guo)等。中(zhong)國(guo)(guo)(guo)(guo)(guo)硅(gui)(gui)橡(xiang)膠(jiao)(jiao)的(de)工業(ye)化研究始于1957年,多家研究所和企業(ye)陸續開(kai)發出各(ge)種硅(gui)(gui)橡(xiang)膠(jiao)(jiao)。到2003年底,中(zhong)國(guo)(guo)(guo)(guo)(guo)硅(gui)(gui)橡(xiang)膠(jiao)(jiao)生產能(neng)力為(wei)135千(qian)噸,其中(zhong)高(gao)溫膠(jiao)(jiao)100千(qian)噸。
高溫硫化硅橡膠
高(gao)溫硫(liu)化(hua)(hua)硅橡膠(jiao)(jiao)是(shi)(shi)指聚(ju)硅氧烷變成彈性體的(de)過(guo)程是(shi)(shi)經過(guo)高(gao)溫(110-170℃)硫(liu)化(hua)(hua)成型的(de)。它主要以高(gao)分(fen)子(zi)量的(de)聚(ju)甲基乙烯(xi)基硅氧烷為(wei)(wei)生膠(jiao)(jiao),混入補強(qiang)填料(liao)、硫(liu)化(hua)(hua)劑(ji)(ji)等,在(zai)加(jia)(jia)熱加(jia)(jia)壓下硫(liu)化(hua)(hua)成彈性體。硅橡膠(jiao)(jiao)的(de)補強(qiang)主要是(shi)(shi)各(ge)(ge)種(zhong)類型的(de)白炭黑,可使(shi)硫(liu)化(hua)(hua)膠(jiao)(jiao)的(de)強(qiang)度增(zeng)加(jia)(jia)數十倍。有時(shi)為(wei)(wei)了降低成本或改善膠(jiao)(jiao)料(liao)性能(neng)及賦予硫(liu)化(hua)(hua)膠(jiao)(jiao)各(ge)(ge)種(zhong)特(te)殊的(de)性能(neng),也(ye)加(jia)(jia)入相(xiang)應的(de)各(ge)(ge)種(zhong)添加(jia)(jia)劑(ji)(ji)。硫(liu)化(hua)(hua)劑(ji)(ji)是(shi)(shi)各(ge)(ge)種(zhong)有機過(guo)氧化(hua)(hua)物(wu)或加(jia)(jia)成反應催化(hua)(hua)劑(ji)(ji)。
加工成型方(fang)法如圖所示。一(yi)次硫化(hua)(hua)的(de)(de)目的(de)(de)是進行高分(fen)子(zi)鏈(lian)的(de)(de)交聯反應;二次硫化(hua)(hua)的(de)(de)目的(de)(de)是進行補充交聯、驅除硫化(hua)(hua)劑分(fen)解產物(wu)和其(qi)他(ta)揮發(fa)性(xing)化(hua)(hua)合物(wu)以(yi)穩定硫化(hua)(hua)膠的(de)(de)各(ge)項性(xing)能。常用的(de)(de)設備有(you)開放式煉膠機、捏合機及真(zhen)空密煉機。
主要性能
(1)高(gao)溫(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)。硅(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)顯著的(de)(de)特征是高(gao)溫(wen)穩定性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing),雖然常(chang)溫(wen)下(xia)(xia)硅(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)的(de)(de)強(qiang)度(du)(du)僅是天然橡(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)或某些合(he)成橡(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)的(de)(de)一(yi)(yi)(yi)半,但在200℃以上的(de)(de)高(gao)溫(wen)環境下(xia)(xia),硅(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)仍能(neng)(neng)保持(chi)一(yi)(yi)(yi)定的(de)(de)柔韌性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)、回彈性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)和(he)表(biao)面硬度(du)(du),且力(li)學性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)無明顯變化。(2)低溫(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)硅(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)的(de)(de)玻(bo)璃化溫(wen)度(du)(du)一(yi)(yi)(yi)般為-70~-50℃,特殊配(pei)方可達-100℃,表(biao)明其低溫(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)優異。這對(dui)(dui)(dui)航(hang)空、宇(yu)航(hang)工業的(de)(de)意義(yi)重大(da)。(3)耐(nai)(nai)候性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)硅(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)中Si-O-Si鍵對(dui)(dui)(dui)氧、臭氧及紫外線(xian)等(deng)十分穩定,在不(bu)加任何添(tian)加劑的(de)(de)情況(kuang)下(xia)(xia),就具(ju)有(you)優良(liang)的(de)(de)耐(nai)(nai)候性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)。(4)電(dian)(dian)氣(qi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)。硅(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)具(ju)有(you)優異的(de)(de)絕(jue)緣性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng),耐(nai)(nai)電(dian)(dian)暈性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)和(he)耐(nai)(nai)電(dian)(dian)弧性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)也非(fei)(fei)常(chang)好(hao)。(5)物(wu)理(li)機械性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)。硅(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)常(chang)溫(wen)下(xia)(xia)的(de)(de)物(wu)理(li)機械性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)比通(tong)(tong)用橡(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)差(cha),但在150℃的(de)(de)高(gao)溫(wen)和(he)-50℃的(de)(de)低溫(wen)下(xia)(xia),其物(wu)理(li)機械性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)優于(yu)通(tong)(tong)用橡(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)。(6)耐(nai)(nai)油及化學試劑性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)。普通(tong)(tong)硅(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)具(ju)有(you)中等(deng)的(de)(de)耐(nai)(nai)油、耐(nai)(nai)溶劑性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)。(7)氣(qi)體(ti)透過(guo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)。室(shi)溫(wen)下(xia)(xia)硅(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)對(dui)(dui)(dui)空氣(qi)、氮、氧、二氧化碳等(deng)氣(qi)體(ti)的(de)(de)透氣(qi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)比天然橡(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)高(gao)出30-50倍。(8)生(sheng)理(li)惰性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)。硅(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao)(jiao)(jiao)無毒(du),無味,無嗅,與人(ren)體(ti)組(zu)織(zhi)不(bu)粘連,具(ju)有(you)抗凝血作(zuo)用,對(dui)(dui)(dui)肌體(ti)組(zu)織(zhi)的(de)(de)反應性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)非(fei)(fei)常(chang)少(shao)。特別(bie)適合(he)作(zuo)為醫用材料(liao)。
硅橡膠的用量
據(ju)中(zhong)國汽(qi)(qi)(qi)車(che)工(gong)(gong)業(ye)協會統計,2012年,汽(qi)(qi)(qi)車(che)產(chan)銷分別(bie)達到1927.18萬(wan)輛和(he)1930.64萬(wan)輛,同比分別(bie)增(zeng)長(chang)4.63%和(he)4.33%,汽(qi)(qi)(qi)車(che)工(gong)(gong)業(ye)硅(gui)(gui)橡(xiang)膠(jiao)的(de)用(yong)(yong)(yong)量(liang)約達2.0萬(wan)t。根據(ju)觀研天下的(de)新研究,增(zeng)加有(you)機(ji)硅(gui)(gui)材料(liao)在汽(qi)(qi)(qi)車(che)零部(bu)(bu)件方面的(de)用(yong)(yong)(yong)量(liang),可以大幅度提高汽(qi)(qi)(qi)車(che)的(de)安全性能(neng),因此(ci),汽(qi)(qi)(qi)車(che)產(chan)量(liang)和(he)單(dan)車(che)用(yong)(yong)(yong)量(liang)水平(ping)的(de)提高都將(jiang)推動汽(qi)(qi)(qi)車(che)工(gong)(gong)業(ye)對(dui)硅(gui)(gui)橡(xiang)膠(jiao)需(xu)求的(de)增(zeng)加。國家鼓勵自主(zhu)(zhu)品牌(pai)的(de)汽(qi)(qi)(qi)車(che)發展,關鍵汽(qi)(qi)(qi)車(che)零部(bu)(bu)件實(shi)現(xian)自主(zhu)(zhu)化,《2012年度黨政(zheng)機(ji)關公務用(yong)(yong)(yong)車(che)選用(yong)(yong)(yong)車(che)型目(mu)錄(征(zheng)求意見稿)》為(wei)自主(zhu)(zhu)品牌(pai)擴大在政(zheng)府(fu)(fu)采購(gou)的(de)市場份額,為(wei)改變目(mu)前國內(nei)政(zheng)府(fu)(fu)采購(gou)以合資(zi)品牌(pai)產(chan)品為(wei)主(zhu)(zhu)的(de)局(ju)面提供(gong)了保障。促進自主(zhu)(zhu)品牌(pai)發展,國產(chan)汽(qi)(qi)(qi)車(che)業(ye)的(de)繁榮將(jiang)為(wei)汽(qi)(qi)(qi)車(che)膠(jiao)的(de)應用(yong)(yong)(yong)提供(gong)有(you)力保障。預(yu)測未來3年,我(wo)國室溫硫化硅(gui)(gui)橡(xiang)膠(jiao)在汽(qi)(qi)(qi)車(che)行業(ye)將(jiang)以年均20%增(zeng)長(chang)。
此外,硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)是(shi)重要的非(fei)石(shi)油(you)(you)基(ji)合成橡(xiang)(xiang)膠(jiao)(jiao),約占非(fei)石(shi)油(you)(you)基(ji)合成橡(xiang)(xiang)膠(jiao)(jiao)消費量的98%。但因為(wei)(wei)石(shi)油(you)(you)價格的大(da)幅上漲,同時我(wo)國(guo)在硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)的關(guan)鍵(jian)原(yuan)料有(you)機(ji)硅(gui)(gui)單(dan)體的生產技術方面(mian)取(qu)得(de)突破,有(you)機(ji)硅(gui)(gui)單(dan)體的生產技術在2005年前(qian)被幾家跨國(guo)公司壟斷,但目(mu)前(qian)我(wo)國(guo)已(yi)發展(zhan)成為(wei)(wei)全球有(you)機(ji)硅(gui)(gui)單(dan)體第1大(da)國(guo),這2個方面(mian)原(yuan)因使(shi)硅(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)的價格從2011年起開始(shi)(shi)低于石(shi)油(you)(you)基(ji)合成橡(xiang)(xiang)膠(jiao)(jiao),僅約為(wei)(wei)大(da)宗石(shi)油(you)(you)基(ji)橡(xiang)(xiang)膠(jiao)(jiao)的80%~90%,成為(wei)(wei)廉價的合成橡(xiang)(xiang)膠(jiao)(jiao),并開始(shi)(shi)大(da)規模替(ti)代石(shi)油(you)(you)基(ji)合成橡(xiang)(xiang)膠(jiao)(jiao)。這將極大(da)拓展(zhan)有(you)機(ji)硅(gui)(gui)產業(ye)的市場(chang)空間(jian),同時將帶動硅(gui)(gui)油(you)(you)、硅(gui)(gui)烷偶聯劑和硅(gui)(gui)樹脂等其他有(you)機(ji)硅(gui)(gui)產品的消費。