
硅橡膠是指主鏈由硅(gui)(gui)(gui)(gui)(gui)和(he)(he)氧原子交(jiao)替構成(cheng),硅(gui)(gui)(gui)(gui)(gui)原子上通(tong)常連有兩個有機基(ji)團的(de)(de)(de)橡(xiang)(xiang)膠(jiao)(jiao)。普(pu)通(tong)的(de)(de)(de)硅(gui)(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)主要由含甲基(ji)和(he)(he)少量乙(yi)烯基(ji)的(de)(de)(de)硅(gui)(gui)(gui)(gui)(gui)氧鏈節組成(cheng)。苯基(ji)的(de)(de)(de)引(yin)入可提高(gao)硅(gui)(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)的(de)(de)(de)耐(nai)(nai)高(gao)、低(di)溫性(xing)(xing)能(neng),三氟丙(bing)基(ji)及(ji)氰基(ji)的(de)(de)(de)引(yin)入則可提高(gao)硅(gui)(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)的(de)(de)(de)耐(nai)(nai)溫及(ji)耐(nai)(nai)油性(xing)(xing)能(neng)。硅(gui)(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)耐(nai)(nai)低(di)溫性(xing)(xing)能(neng)良好,一(yi)般在-55℃下仍能(neng)工作(zuo)。引(yin)入苯基(ji)后(hou),可達-73℃。硅(gui)(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)的(de)(de)(de)耐(nai)(nai)熱性(xing)(xing)能(neng)也很突出(chu),在180℃下可長期工作(zuo),稍高(gao)于200℃也能(neng)承受數周或更(geng)長時間(jian)仍有彈性(xing)(xing),瞬時可耐(nai)(nai)300℃以(yi)上的(de)(de)(de)高(gao)溫。硅(gui)(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)的(de)(de)(de)透氣(qi)性(xing)(xing)好,氧氣(qi)透過率在合(he)成(cheng)聚合(he)物中是較高(gao)的(de)(de)(de)。此外,硅(gui)(gui)(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)還(huan)具有生(sheng)理(li)惰性(xing)(xing)、不(bu)會(hui)導致凝血的(de)(de)(de)突出(chu)特(te)性(xing)(xing),因此在醫用領域應用廣泛(fan)。
主要品種
硅橡(xiang)(xiang)膠(jiao)(jiao)分(fen)類的(de)方法(fa)很多,通(tong)常按(an)(an)固(gu)化前的(de)形態分(fen)為固(gu)體(ti)硅橡(xiang)(xiang)膠(jiao)(jiao)和(he)液體(ti)硅橡(xiang)(xiang)膠(jiao)(jiao);按(an)(an)硫化溫度分(fen)為室溫硫化硅橡(xiang)(xiang)膠(jiao)(jiao),高溫硫化硅橡(xiang)(xiang)膠(jiao)(jiao);按(an)(an)所用(yong)單體(ti)的(de)不同,可(ke)分(fen)為甲基(ji)乙烯(xi)基(ji)硅橡(xiang)(xiang)膠(jiao)(jiao),甲基(ji)苯基(ji)乙烯(xi)基(ji)硅橡(xiang)(xiang)膠(jiao)(jiao)、氟硅,腈硅橡(xiang)(xiang)膠(jiao)(jiao)等(deng);按(an)(an)性能和(he)用(yong)途的(de)不同又可(ke)分(fen)為通(tong)用(yong)型(xing)(xing)(xing)(xing)、超耐低溫型(xing)(xing)(xing)(xing)、超耐高溫型(xing)(xing)(xing)(xing)、高強力型(xing)(xing)(xing)(xing)、耐油型(xing)(xing)(xing)(xing)、醫用(yong)型(xing)(xing)(xing)(xing)等(deng)等(deng)。
發展史
硅(gui)橡膠(jiao)(jiao)早期(qi)是由美(mei)國(guo)以三氯(lv)化(hua)鐵為催化(hua)劑合(he)成(cheng)(cheng)的(de)(de)(de)(de)。1945年(nian),硅(gui)橡膠(jiao)(jiao)產(chan)品問世。1948年(nian),采用高(gao)比表(biao)面積(ji)的(de)(de)(de)(de)氣相法白炭黑補(bu)強(qiang)的(de)(de)(de)(de)硅(gui)橡膠(jiao)(jiao)研制成(cheng)(cheng)功,使硅(gui)橡膠(jiao)(jiao)的(de)(de)(de)(de)性能躍升(sheng)到(dao)(dao)實用階段,奠定了現代硅(gui)橡膠(jiao)(jiao)生產(chan)技術的(de)(de)(de)(de)基礎。從(cong)二(er)甲基二(er)氯(lv)硅(gui)烷合(he)成(cheng)(cheng)開始(shi)生產(chan)硅(gui)橡膠(jiao)(jiao)的(de)(de)(de)(de)國(guo)家有美(mei)國(guo)。俄羅(luo)斯(si)、德國(guo)、日本、韓國(guo)和中(zhong)國(guo)等。中(zhong)國(guo)硅(gui)橡膠(jiao)(jiao)的(de)(de)(de)(de)工業化(hua)研究始(shi)于1957年(nian),多家研究所和企業陸續開發出各(ge)種硅(gui)橡膠(jiao)(jiao)。到(dao)(dao)2003年(nian)底,中(zhong)國(guo)硅(gui)橡膠(jiao)(jiao)生產(chan)能力(li)為135千(qian)噸,其中(zhong)高(gao)溫(wen)膠(jiao)(jiao)100千(qian)噸。
高溫硫化硅橡膠
高溫硫(liu)(liu)化(hua)(hua)硅(gui)橡膠(jiao)(jiao)是指聚硅(gui)氧(yang)烷變(bian)成(cheng)彈性(xing)體的過程是經(jing)過高溫(110-170℃)硫(liu)(liu)化(hua)(hua)成(cheng)型的。它主(zhu)要以高分子量的聚甲基乙烯基硅(gui)氧(yang)烷為(wei)生膠(jiao)(jiao),混入(ru)補強(qiang)填(tian)料、硫(liu)(liu)化(hua)(hua)劑(ji)等,在加(jia)熱加(jia)壓下硫(liu)(liu)化(hua)(hua)成(cheng)彈性(xing)體。硅(gui)橡膠(jiao)(jiao)的補強(qiang)主(zhu)要是各(ge)種類型的白炭(tan)黑,可使硫(liu)(liu)化(hua)(hua)膠(jiao)(jiao)的強(qiang)度增加(jia)數十(shi)倍(bei)。有(you)時為(wei)了(le)降低成(cheng)本或改善膠(jiao)(jiao)料性(xing)能及(ji)賦予(yu)硫(liu)(liu)化(hua)(hua)膠(jiao)(jiao)各(ge)種特殊的性(xing)能,也(ye)加(jia)入(ru)相應的各(ge)種添加(jia)劑(ji)。硫(liu)(liu)化(hua)(hua)劑(ji)是各(ge)種有(you)機(ji)過氧(yang)化(hua)(hua)物或加(jia)成(cheng)反應催(cui)化(hua)(hua)劑(ji)。
加(jia)工成型方法如圖所示。一次(ci)硫(liu)化(hua)的(de)(de)(de)(de)目(mu)的(de)(de)(de)(de)是進(jin)行高分子鏈(lian)的(de)(de)(de)(de)交(jiao)聯反應;二次(ci)硫(liu)化(hua)的(de)(de)(de)(de)目(mu)的(de)(de)(de)(de)是進(jin)行補(bu)充交(jiao)聯、驅除(chu)硫(liu)化(hua)劑分解(jie)產物(wu)和其他揮發(fa)性(xing)化(hua)合物(wu)以(yi)穩(wen)定硫(liu)化(hua)膠(jiao)的(de)(de)(de)(de)各項性(xing)能(neng)。常用的(de)(de)(de)(de)設備有開(kai)放式煉膠(jiao)機、捏(nie)合機及真(zhen)空(kong)密煉機。
主要性能
(1)高溫(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)。硅(gui)橡(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)顯(xian)著的(de)(de)(de)特征是高溫(wen)(wen)穩(wen)定性(xing)(xing)(xing)(xing)(xing)(xing)(xing),雖然常(chang)溫(wen)(wen)下(xia)(xia)硅(gui)橡(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)的(de)(de)(de)強度僅是天(tian)然橡(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)或(huo)某些合成橡(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)的(de)(de)(de)一半(ban),但(dan)在200℃以上的(de)(de)(de)高溫(wen)(wen)環(huan)境下(xia)(xia),硅(gui)橡(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)仍能(neng)(neng)保持一定的(de)(de)(de)柔韌性(xing)(xing)(xing)(xing)(xing)(xing)(xing)、回彈性(xing)(xing)(xing)(xing)(xing)(xing)(xing)和表(biao)面硬度,且力學性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)無明(ming)顯(xian)變化(hua)。(2)低溫(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)硅(gui)橡(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)的(de)(de)(de)玻璃(li)化(hua)溫(wen)(wen)度一般為(wei)-70~-50℃,特殊配方(fang)可達-100℃,表(biao)明(ming)其低溫(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)優(you)異。這對(dui)航(hang)空、宇航(hang)工業的(de)(de)(de)意義重(zhong)大。(3)耐(nai)(nai)(nai)(nai)候性(xing)(xing)(xing)(xing)(xing)(xing)(xing)硅(gui)橡(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)中(zhong)Si-O-Si鍵(jian)對(dui)氧(yang)(yang)、臭氧(yang)(yang)及紫外線(xian)等十分穩(wen)定,在不加(jia)任何添加(jia)劑(ji)的(de)(de)(de)情況下(xia)(xia),就具(ju)有(you)優(you)良(liang)的(de)(de)(de)耐(nai)(nai)(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)橡(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)具(ju)有(you)優(you)異的(de)(de)(de)絕緣性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng),耐(nai)(nai)(nai)(nai)電(dian)暈性(xing)(xing)(xing)(xing)(xing)(xing)(xing)和耐(nai)(nai)(nai)(nai)電(dian)弧性(xing)(xing)(xing)(xing)(xing)(xing)(xing)也非(fei)常(chang)好。(5)物理(li)機械性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)。硅(gui)橡(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)常(chang)溫(wen)(wen)下(xia)(xia)的(de)(de)(de)物理(li)機械性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)比(bi)通用(yong)橡(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)差(cha),但(dan)在150℃的(de)(de)(de)高溫(wen)(wen)和-50℃的(de)(de)(de)低溫(wen)(wen)下(xia)(xia),其物理(li)機械性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)優(you)于(yu)通用(yong)橡(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)。(6)耐(nai)(nai)(nai)(nai)油及化(hua)學試(shi)劑(ji)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)。普通硅(gui)橡(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)具(ju)有(you)中(zhong)等的(de)(de)(de)耐(nai)(nai)(nai)(nai)油、耐(nai)(nai)(nai)(nai)溶劑(ji)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)。(7)氣體透過性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)。室溫(wen)(wen)下(xia)(xia)硅(gui)橡(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)對(dui)空氣、氮、氧(yang)(yang)、二氧(yang)(yang)化(hua)碳等氣體的(de)(de)(de)透氣性(xing)(xing)(xing)(xing)(xing)(xing)(xing)比(bi)天(tian)然橡(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)高出(chu)30-50倍。(8)生理(li)惰性(xing)(xing)(xing)(xing)(xing)(xing)(xing)。硅(gui)橡(xiang)(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)無毒,無味,無嗅,與人體組(zu)織(zhi)不粘連,具(ju)有(you)抗凝血作用(yong),對(dui)肌體組(zu)織(zhi)的(de)(de)(de)反(fan)應性(xing)(xing)(xing)(xing)(xing)(xing)(xing)非(fei)常(chang)少。特別適合作為(wei)醫用(yong)材料。
硅橡膠的用量
據中國(guo)(guo)汽(qi)(qi)(qi)(qi)(qi)車(che)(che)工(gong)業(ye)協會統(tong)計,2012年,汽(qi)(qi)(qi)(qi)(qi)車(che)(che)產銷分(fen)別(bie)達(da)到1927.18萬輛和1930.64萬輛,同比分(fen)別(bie)增(zeng)長(chang)4.63%和4.33%,汽(qi)(qi)(qi)(qi)(qi)車(che)(che)工(gong)業(ye)硅(gui)(gui)橡膠(jiao)的(de)(de)用(yong)(yong)量約達(da)2.0萬t。根(gen)據觀研天(tian)下(xia)的(de)(de)新(xin)研究,增(zeng)加有機(ji)硅(gui)(gui)材料在汽(qi)(qi)(qi)(qi)(qi)車(che)(che)零部件方面(mian)的(de)(de)用(yong)(yong)量,可(ke)以(yi)大幅度提(ti)高汽(qi)(qi)(qi)(qi)(qi)車(che)(che)的(de)(de)安全性(xing)能,因此,汽(qi)(qi)(qi)(qi)(qi)車(che)(che)產量和單車(che)(che)用(yong)(yong)量水平的(de)(de)提(ti)高都將推(tui)動汽(qi)(qi)(qi)(qi)(qi)車(che)(che)工(gong)業(ye)對(dui)硅(gui)(gui)橡膠(jiao)需求的(de)(de)增(zeng)加。國(guo)(guo)家鼓勵自(zi)主(zhu)(zhu)品(pin)牌(pai)的(de)(de)汽(qi)(qi)(qi)(qi)(qi)車(che)(che)發展(zhan),關鍵汽(qi)(qi)(qi)(qi)(qi)車(che)(che)零部件實(shi)現自(zi)主(zhu)(zhu)化,《2012年度黨政機(ji)關公務用(yong)(yong)車(che)(che)選用(yong)(yong)車(che)(che)型目(mu)錄(征求意見稿(gao))》為(wei)自(zi)主(zhu)(zhu)品(pin)牌(pai)擴(kuo)大在政府(fu)采購(gou)的(de)(de)市(shi)場份額,為(wei)改變(bian)目(mu)前(qian)國(guo)(guo)內政府(fu)采購(gou)以(yi)合資品(pin)牌(pai)產品(pin)為(wei)主(zhu)(zhu)的(de)(de)局面(mian)提(ti)供(gong)(gong)了保障(zhang)。促進自(zi)主(zhu)(zhu)品(pin)牌(pai)發展(zhan),國(guo)(guo)產汽(qi)(qi)(qi)(qi)(qi)車(che)(che)業(ye)的(de)(de)繁榮將為(wei)汽(qi)(qi)(qi)(qi)(qi)車(che)(che)膠(jiao)的(de)(de)應用(yong)(yong)提(ti)供(gong)(gong)有力保障(zhang)。預測未來3年,我國(guo)(guo)室溫硫(liu)化硅(gui)(gui)橡膠(jiao)在汽(qi)(qi)(qi)(qi)(qi)車(che)(che)行(xing)業(ye)將以(yi)年均20%增(zeng)長(chang)。
此(ci)外,硅(gui)(gui)(gui)橡(xiang)膠(jiao)是重要的非石(shi)(shi)油(you)基(ji)(ji)合(he)成(cheng)橡(xiang)膠(jiao),約(yue)(yue)占非石(shi)(shi)油(you)基(ji)(ji)合(he)成(cheng)橡(xiang)膠(jiao)消費量的98%。但因為石(shi)(shi)油(you)價格(ge)的大(da)幅上漲,同時我(wo)國(guo)在硅(gui)(gui)(gui)橡(xiang)膠(jiao)的關鍵(jian)原料有機硅(gui)(gui)(gui)單體(ti)(ti)的生產技(ji)(ji)術方面取得突破,有機硅(gui)(gui)(gui)單體(ti)(ti)的生產技(ji)(ji)術在2005年(nian)前(qian)被(bei)幾家(jia)跨國(guo)公(gong)司壟(long)斷,但目前(qian)我(wo)國(guo)已(yi)發(fa)展(zhan)(zhan)成(cheng)為全球有機硅(gui)(gui)(gui)單體(ti)(ti)第1大(da)國(guo),這2個(ge)方面原因使(shi)硅(gui)(gui)(gui)橡(xiang)膠(jiao)的價格(ge)從2011年(nian)起(qi)開始(shi)低(di)于(yu)石(shi)(shi)油(you)基(ji)(ji)合(he)成(cheng)橡(xiang)膠(jiao),僅約(yue)(yue)為大(da)宗石(shi)(shi)油(you)基(ji)(ji)橡(xiang)膠(jiao)的80%~90%,成(cheng)為廉價的合(he)成(cheng)橡(xiang)膠(jiao),并開始(shi)大(da)規模替代石(shi)(shi)油(you)基(ji)(ji)合(he)成(cheng)橡(xiang)膠(jiao)。這將極(ji)大(da)拓展(zhan)(zhan)有機硅(gui)(gui)(gui)產業的市(shi)場空間,同時將帶動硅(gui)(gui)(gui)油(you)、硅(gui)(gui)(gui)烷偶(ou)聯劑和硅(gui)(gui)(gui)樹脂等其他(ta)有機硅(gui)(gui)(gui)產品的消費。