
硅橡膠是指(zhi)主鏈(lian)由硅(gui)(gui)和氧(yang)原(yuan)子交替構(gou)成(cheng),硅(gui)(gui)原(yuan)子上通(tong)常連有(you)兩個有(you)機(ji)基(ji)(ji)(ji)(ji)團的(de)(de)(de)(de)(de)(de)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)。普通(tong)的(de)(de)(de)(de)(de)(de)硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)主要由含甲基(ji)(ji)(ji)(ji)和少(shao)量(liang)乙(yi)烯基(ji)(ji)(ji)(ji)的(de)(de)(de)(de)(de)(de)硅(gui)(gui)氧(yang)鏈(lian)節組成(cheng)。苯(ben)基(ji)(ji)(ji)(ji)的(de)(de)(de)(de)(de)(de)引入(ru)可提高硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)的(de)(de)(de)(de)(de)(de)耐高、低溫(wen)性(xing)能(neng),三氟(fu)丙(bing)基(ji)(ji)(ji)(ji)及氰基(ji)(ji)(ji)(ji)的(de)(de)(de)(de)(de)(de)引入(ru)則可提高硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)的(de)(de)(de)(de)(de)(de)耐溫(wen)及耐油性(xing)能(neng)。硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)耐低溫(wen)性(xing)能(neng)良好,一般在(zai)-55℃下(xia)仍能(neng)工(gong)作。引入(ru)苯(ben)基(ji)(ji)(ji)(ji)后(hou),可達-73℃。硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)的(de)(de)(de)(de)(de)(de)耐熱性(xing)能(neng)也很(hen)突出(chu),在(zai)180℃下(xia)可長(chang)期工(gong)作,稍高于200℃也能(neng)承受數(shu)周或更(geng)長(chang)時(shi)間仍有(you)彈性(xing),瞬時(shi)可耐300℃以上的(de)(de)(de)(de)(de)(de)高溫(wen)。硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)的(de)(de)(de)(de)(de)(de)透氣性(xing)好,氧(yang)氣透過(guo)率在(zai)合成(cheng)聚合物中是較高的(de)(de)(de)(de)(de)(de)。此(ci)外,硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)還(huan)具有(you)生(sheng)理惰性(xing)、不(bu)會(hui)導致凝血(xue)的(de)(de)(de)(de)(de)(de)突出(chu)特性(xing),因(yin)此(ci)在(zai)醫(yi)用領域應用廣泛。
主要品種
硅(gui)(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao)(jiao)分類的方法很多,通常按固化(hua)(hua)前的形態分為固體(ti)(ti)硅(gui)(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao)(jiao)和液體(ti)(ti)硅(gui)(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao)(jiao);按硫(liu)化(hua)(hua)溫(wen)(wen)度分為室溫(wen)(wen)硫(liu)化(hua)(hua)硅(gui)(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao)(jiao),高(gao)溫(wen)(wen)硫(liu)化(hua)(hua)硅(gui)(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao)(jiao);按所用(yong)(yong)單體(ti)(ti)的不同,可分為甲基(ji)乙(yi)(yi)烯基(ji)硅(gui)(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao)(jiao),甲基(ji)苯基(ji)乙(yi)(yi)烯基(ji)硅(gui)(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao)(jiao)、氟硅(gui)(gui)(gui)(gui),腈硅(gui)(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao)(jiao)等;按性能和用(yong)(yong)途(tu)的不同又可分為通用(yong)(yong)型(xing)(xing)、超耐(nai)低溫(wen)(wen)型(xing)(xing)、超耐(nai)高(gao)溫(wen)(wen)型(xing)(xing)、高(gao)強(qiang)力型(xing)(xing)、耐(nai)油型(xing)(xing)、醫(yi)用(yong)(yong)型(xing)(xing)等等。
發展史
硅(gui)橡(xiang)(xiang)膠(jiao)早期是由美國(guo)以三(san)氯(lv)化(hua)鐵為催化(hua)劑合(he)(he)成的。1945年,硅(gui)橡(xiang)(xiang)膠(jiao)產(chan)(chan)品問世。1948年,采(cai)用(yong)高比表(biao)面積的氣相法白炭黑(hei)補(bu)強的硅(gui)橡(xiang)(xiang)膠(jiao)研制成功,使硅(gui)橡(xiang)(xiang)膠(jiao)的性能(neng)躍升到實(shi)用(yong)階段,奠(dian)定了現代(dai)硅(gui)橡(xiang)(xiang)膠(jiao)生(sheng)產(chan)(chan)技術的基礎(chu)。從二(er)甲基二(er)氯(lv)硅(gui)烷合(he)(he)成開始生(sheng)產(chan)(chan)硅(gui)橡(xiang)(xiang)膠(jiao)的國(guo)家有美國(guo)。俄羅(luo)斯、德(de)國(guo)、日本、韓國(guo)和中國(guo)等。中國(guo)硅(gui)橡(xiang)(xiang)膠(jiao)的工業化(hua)研究始于1957年,多家研究所(suo)和企業陸續開發(fa)出(chu)各種硅(gui)橡(xiang)(xiang)膠(jiao)。到2003年底,中國(guo)硅(gui)橡(xiang)(xiang)膠(jiao)生(sheng)產(chan)(chan)能(neng)力為135千噸,其(qi)中高溫膠(jiao)100千噸。
高溫硫化硅橡膠
高溫(wen)硫(liu)化(hua)(hua)硅(gui)橡膠(jiao)是(shi)指聚硅(gui)氧烷(wan)變(bian)成(cheng)彈(dan)性(xing)體的(de)過(guo)(guo)程是(shi)經(jing)過(guo)(guo)高溫(wen)(110-170℃)硫(liu)化(hua)(hua)成(cheng)型的(de)。它主要(yao)以高分子量(liang)的(de)聚甲基乙烯(xi)基硅(gui)氧烷(wan)為(wei)生膠(jiao),混入補強(qiang)填(tian)料、硫(liu)化(hua)(hua)劑(ji)等(deng),在(zai)加熱加壓下(xia)硫(liu)化(hua)(hua)成(cheng)彈(dan)性(xing)體。硅(gui)橡膠(jiao)的(de)補強(qiang)主要(yao)是(shi)各(ge)(ge)(ge)種類型的(de)白(bai)炭黑(hei),可(ke)使硫(liu)化(hua)(hua)膠(jiao)的(de)強(qiang)度增(zeng)加數(shu)十倍(bei)。有(you)時為(wei)了降低成(cheng)本或改善膠(jiao)料性(xing)能及賦(fu)予硫(liu)化(hua)(hua)膠(jiao)各(ge)(ge)(ge)種特殊的(de)性(xing)能,也加入相應(ying)的(de)各(ge)(ge)(ge)種添加劑(ji)。硫(liu)化(hua)(hua)劑(ji)是(shi)各(ge)(ge)(ge)種有(you)機過(guo)(guo)氧化(hua)(hua)物或加成(cheng)反應(ying)催化(hua)(hua)劑(ji)。
加工成型方法(fa)如圖所示。一次硫(liu)化(hua)(hua)的目(mu)的是進行高分子鏈的交聯(lian)反應;二次硫(liu)化(hua)(hua)的目(mu)的是進行補充交聯(lian)、驅除硫(liu)化(hua)(hua)劑分解產物和其他揮發性化(hua)(hua)合(he)(he)物以穩(wen)定硫(liu)化(hua)(hua)膠(jiao)的各項性能(neng)。常用(yong)的設備(bei)有開放式煉膠(jiao)機(ji)、捏合(he)(he)機(ji)及真空(kong)密(mi)煉機(ji)。
主要性能
(1)高(gao)溫(wen)(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)。硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)顯(xian)著的特征是(shi)高(gao)溫(wen)(wen)(wen)穩定(ding)(ding)性(xing)(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)(jiao)的強度(du)僅是(shi)天然橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)或某些(xie)合成橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)的一(yi)半,但在200℃以上的高(gao)溫(wen)(wen)(wen)環(huan)境下(xia),硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)仍(reng)能(neng)(neng)保(bao)持(chi)一(yi)定(ding)(ding)的柔韌性(xing)(xing)(xing)(xing)(xing)(xing)(xing)、回彈性(xing)(xing)(xing)(xing)(xing)(xing)(xing)和(he)表(biao)面硬度(du),且力學(xue)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)無明顯(xian)變化。(2)低溫(wen)(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)的玻璃化溫(wen)(wen)(wen)度(du)一(yi)般(ban)為-70~-50℃,特殊配方可達-100℃,表(biao)明其(qi)低溫(wen)(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)優異(yi)。這對(dui)航空、宇航工(gong)業的意義(yi)重大。(3)耐(nai)(nai)候性(xing)(xing)(xing)(xing)(xing)(xing)(xing)硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)中Si-O-Si鍵對(dui)氧(yang)、臭氧(yang)及紫外線等十分穩定(ding)(ding),在不加任何添(tian)加劑(ji)(ji)的情(qing)況下(xia),就具有(you)(you)優良的耐(nai)(nai)候性(xing)(xing)(xing)(xing)(xing)(xing)(xing)。(4)電(dian)氣性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)。硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)具有(you)(you)優異(yi)的絕緣性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng),耐(nai)(nai)電(dian)暈(yun)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)和(he)耐(nai)(nai)電(dian)弧性(xing)(xing)(xing)(xing)(xing)(xing)(xing)也非(fei)常(chang)好(hao)。(5)物(wu)(wu)理機(ji)械性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)。硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)常(chang)溫(wen)(wen)(wen)下(xia)的物(wu)(wu)理機(ji)械性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)比通(tong)用(yong)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)差,但在150℃的高(gao)溫(wen)(wen)(wen)和(he)-50℃的低溫(wen)(wen)(wen)下(xia),其(qi)物(wu)(wu)理機(ji)械性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)優于(yu)通(tong)用(yong)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)。(6)耐(nai)(nai)油及化學(xue)試劑(ji)(ji)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)。普通(tong)硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)具有(you)(you)中等的耐(nai)(nai)油、耐(nai)(nai)溶劑(ji)(ji)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)。(7)氣體(ti)(ti)透過性(xing)(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)(jiao)對(dui)空氣、氮、氧(yang)、二氧(yang)化碳等氣體(ti)(ti)的透氣性(xing)(xing)(xing)(xing)(xing)(xing)(xing)比天然橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)高(gao)出30-50倍(bei)。(8)生理惰性(xing)(xing)(xing)(xing)(xing)(xing)(xing)。硅(gui)(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)無毒,無味,無嗅,與(yu)人(ren)體(ti)(ti)組織不粘(zhan)連(lian),具有(you)(you)抗凝血作用(yong),對(dui)肌體(ti)(ti)組織的反(fan)應性(xing)(xing)(xing)(xing)(xing)(xing)(xing)非(fei)常(chang)少。特別適合作為醫用(yong)材料。
硅橡膠的用量
據中國汽(qi)(qi)(qi)(qi)車(che)工業(ye)(ye)(ye)協會統(tong)計(ji),2012年(nian)(nian),汽(qi)(qi)(qi)(qi)車(che)產(chan)銷分(fen)別達到1927.18萬(wan)輛和(he)(he)1930.64萬(wan)輛,同比分(fen)別增長4.63%和(he)(he)4.33%,汽(qi)(qi)(qi)(qi)車(che)工業(ye)(ye)(ye)硅橡(xiang)(xiang)膠(jiao)的(de)用(yong)量(liang)約達2.0萬(wan)t。根據觀研天下的(de)新研究,增加有機(ji)硅材(cai)料在汽(qi)(qi)(qi)(qi)車(che)零(ling)部(bu)件方面的(de)用(yong)量(liang),可以大(da)幅度提(ti)高汽(qi)(qi)(qi)(qi)車(che)的(de)安全性能,因此(ci),汽(qi)(qi)(qi)(qi)車(che)產(chan)量(liang)和(he)(he)單車(che)用(yong)量(liang)水平(ping)的(de)提(ti)高都將推動汽(qi)(qi)(qi)(qi)車(che)工業(ye)(ye)(ye)對硅橡(xiang)(xiang)膠(jiao)需求的(de)增加。國家鼓勵自(zi)(zi)(zi)主(zhu)(zhu)品(pin)牌(pai)的(de)汽(qi)(qi)(qi)(qi)車(che)發展(zhan),關鍵汽(qi)(qi)(qi)(qi)車(che)零(ling)部(bu)件實現自(zi)(zi)(zi)主(zhu)(zhu)化(hua),《2012年(nian)(nian)度黨政(zheng)機(ji)關公務用(yong)車(che)選用(yong)車(che)型目(mu)(mu)錄(征求意見(jian)稿)》為自(zi)(zi)(zi)主(zhu)(zhu)品(pin)牌(pai)擴大(da)在政(zheng)府(fu)采(cai)購的(de)市場份額,為改變目(mu)(mu)前國內政(zheng)府(fu)采(cai)購以合資品(pin)牌(pai)產(chan)品(pin)為主(zhu)(zhu)的(de)局面提(ti)供了保障。促進自(zi)(zi)(zi)主(zhu)(zhu)品(pin)牌(pai)發展(zhan),國產(chan)汽(qi)(qi)(qi)(qi)車(che)業(ye)(ye)(ye)的(de)繁榮將為汽(qi)(qi)(qi)(qi)車(che)膠(jiao)的(de)應(ying)用(yong)提(ti)供有力保障。預(yu)測未來3年(nian)(nian),我國室(shi)溫(wen)硫化(hua)硅橡(xiang)(xiang)膠(jiao)在汽(qi)(qi)(qi)(qi)車(che)行業(ye)(ye)(ye)將以年(nian)(nian)均20%增長。
此外,硅(gui)(gui)橡(xiang)(xiang)膠(jiao)是重要的(de)(de)(de)非石(shi)(shi)油(you)(you)基合(he)(he)成(cheng)橡(xiang)(xiang)膠(jiao),約占非石(shi)(shi)油(you)(you)基合(he)(he)成(cheng)橡(xiang)(xiang)膠(jiao)消費(fei)量的(de)(de)(de)98%。但因為(wei)(wei)(wei)石(shi)(shi)油(you)(you)價格的(de)(de)(de)大幅上漲,同時我國在硅(gui)(gui)橡(xiang)(xiang)膠(jiao)的(de)(de)(de)關鍵原料(liao)有機硅(gui)(gui)單(dan)體的(de)(de)(de)生產技(ji)術(shu)方面取得(de)突破,有機硅(gui)(gui)單(dan)體的(de)(de)(de)生產技(ji)術(shu)在2005年前被幾家跨國公司(si)壟(long)斷,但目前我國已發展成(cheng)為(wei)(wei)(wei)全球有機硅(gui)(gui)單(dan)體第1大國,這2個方面原因使硅(gui)(gui)橡(xiang)(xiang)膠(jiao)的(de)(de)(de)價格從2011年起開(kai)始低于石(shi)(shi)油(you)(you)基合(he)(he)成(cheng)橡(xiang)(xiang)膠(jiao),僅約為(wei)(wei)(wei)大宗石(shi)(shi)油(you)(you)基橡(xiang)(xiang)膠(jiao)的(de)(de)(de)80%~90%,成(cheng)為(wei)(wei)(wei)廉(lian)價的(de)(de)(de)合(he)(he)成(cheng)橡(xiang)(xiang)膠(jiao),并開(kai)始大規模替代石(shi)(shi)油(you)(you)基合(he)(he)成(cheng)橡(xiang)(xiang)膠(jiao)。這將極大拓展有機硅(gui)(gui)產業的(de)(de)(de)市場空間(jian),同時將帶動硅(gui)(gui)油(you)(you)、硅(gui)(gui)烷(wan)偶聯劑和硅(gui)(gui)樹(shu)脂等其(qi)他有機硅(gui)(gui)產品的(de)(de)(de)消費(fei)。