
硅橡膠是指主(zhu)鏈(lian)由(you)硅(gui)(gui)(gui)和氧(yang)原(yuan)子交(jiao)替構成(cheng)(cheng),硅(gui)(gui)(gui)原(yuan)子上通常連有(you)兩個有(you)機基(ji)團(tuan)的(de)(de)橡膠(jiao)(jiao)。普(pu)通的(de)(de)硅(gui)(gui)(gui)橡膠(jiao)(jiao)主(zhu)要由(you)含甲基(ji)和少量(liang)乙烯基(ji)的(de)(de)硅(gui)(gui)(gui)氧(yang)鏈(lian)節組成(cheng)(cheng)。苯(ben)基(ji)的(de)(de)引入可(ke)提高(gao)(gao)硅(gui)(gui)(gui)橡膠(jiao)(jiao)的(de)(de)耐(nai)(nai)高(gao)(gao)、低(di)溫(wen)性(xing)能(neng)(neng),三氟丙基(ji)及氰基(ji)的(de)(de)引入則可(ke)提高(gao)(gao)硅(gui)(gui)(gui)橡膠(jiao)(jiao)的(de)(de)耐(nai)(nai)溫(wen)及耐(nai)(nai)油性(xing)能(neng)(neng)。硅(gui)(gui)(gui)橡膠(jiao)(jiao)耐(nai)(nai)低(di)溫(wen)性(xing)能(neng)(neng)良(liang)好,一般在(zai)-55℃下仍能(neng)(neng)工(gong)作(zuo)。引入苯(ben)基(ji)后,可(ke)達(da)-73℃。硅(gui)(gui)(gui)橡膠(jiao)(jiao)的(de)(de)耐(nai)(nai)熱(re)性(xing)能(neng)(neng)也很突(tu)出,在(zai)180℃下可(ke)長期(qi)工(gong)作(zuo),稍高(gao)(gao)于200℃也能(neng)(neng)承受數(shu)周或(huo)更長時間(jian)仍有(you)彈性(xing),瞬時可(ke)耐(nai)(nai)300℃以上的(de)(de)高(gao)(gao)溫(wen)。硅(gui)(gui)(gui)橡膠(jiao)(jiao)的(de)(de)透氣性(xing)好,氧(yang)氣透過率在(zai)合成(cheng)(cheng)聚合物中是較高(gao)(gao)的(de)(de)。此(ci)外,硅(gui)(gui)(gui)橡膠(jiao)(jiao)還具有(you)生(sheng)理惰性(xing)、不會導致(zhi)凝(ning)血的(de)(de)突(tu)出特性(xing),因(yin)此(ci)在(zai)醫用(yong)領域應用(yong)廣泛。
主要品種
硅(gui)(gui)橡膠(jiao)分(fen)(fen)類的(de)方法很多,通常按(an)固化(hua)前(qian)的(de)形(xing)態(tai)分(fen)(fen)為固體硅(gui)(gui)橡膠(jiao)和液體硅(gui)(gui)橡膠(jiao);按(an)硫化(hua)溫(wen)(wen)度分(fen)(fen)為室(shi)溫(wen)(wen)硫化(hua)硅(gui)(gui)橡膠(jiao),高溫(wen)(wen)硫化(hua)硅(gui)(gui)橡膠(jiao);按(an)所用(yong)(yong)單體的(de)不(bu)同(tong),可(ke)分(fen)(fen)為甲(jia)基(ji)乙烯基(ji)硅(gui)(gui)橡膠(jiao),甲(jia)基(ji)苯基(ji)乙烯基(ji)硅(gui)(gui)橡膠(jiao)、氟硅(gui)(gui),腈(jing)硅(gui)(gui)橡膠(jiao)等;按(an)性能和用(yong)(yong)途的(de)不(bu)同(tong)又可(ke)分(fen)(fen)為通用(yong)(yong)型(xing)、超耐(nai)低(di)溫(wen)(wen)型(xing)、超耐(nai)高溫(wen)(wen)型(xing)、高強力型(xing)、耐(nai)油型(xing)、醫用(yong)(yong)型(xing)等等。
發展史
硅橡(xiang)(xiang)(xiang)膠(jiao)(jiao)早(zao)期是由美國(guo)(guo)以三氯化鐵(tie)為催化劑合(he)(he)成的(de)。1945年,硅橡(xiang)(xiang)(xiang)膠(jiao)(jiao)產品(pin)問世。1948年,采用高比表(biao)面積的(de)氣相法白炭(tan)黑補強的(de)硅橡(xiang)(xiang)(xiang)膠(jiao)(jiao)研制成功,使硅橡(xiang)(xiang)(xiang)膠(jiao)(jiao)的(de)性能躍升到實用階段,奠定了現(xian)代硅橡(xiang)(xiang)(xiang)膠(jiao)(jiao)生產技(ji)術(shu)的(de)基礎。從二(er)甲(jia)基二(er)氯硅烷(wan)合(he)(he)成開(kai)(kai)始生產硅橡(xiang)(xiang)(xiang)膠(jiao)(jiao)的(de)國(guo)(guo)家(jia)有美國(guo)(guo)。俄羅(luo)斯、德國(guo)(guo)、日本、韓國(guo)(guo)和(he)中(zhong)國(guo)(guo)等(deng)。中(zhong)國(guo)(guo)硅橡(xiang)(xiang)(xiang)膠(jiao)(jiao)的(de)工(gong)業(ye)化研究(jiu)(jiu)始于1957年,多(duo)家(jia)研究(jiu)(jiu)所和(he)企業(ye)陸續開(kai)(kai)發出(chu)各種硅橡(xiang)(xiang)(xiang)膠(jiao)(jiao)。到2003年底(di),中(zhong)國(guo)(guo)硅橡(xiang)(xiang)(xiang)膠(jiao)(jiao)生產能力為135千噸,其中(zhong)高溫膠(jiao)(jiao)100千噸。
高溫硫化硅橡膠
高溫(wen)硫(liu)(liu)化(hua)(hua)(hua)(hua)硅(gui)橡膠(jiao)(jiao)是(shi)指聚(ju)硅(gui)氧(yang)(yang)烷變成(cheng)彈(dan)性(xing)體的(de)過(guo)程是(shi)經(jing)過(guo)高溫(wen)(110-170℃)硫(liu)(liu)化(hua)(hua)(hua)(hua)成(cheng)型的(de)。它主(zhu)要以高分子量的(de)聚(ju)甲基乙烯(xi)基硅(gui)氧(yang)(yang)烷為生膠(jiao)(jiao),混入(ru)補強(qiang)填料、硫(liu)(liu)化(hua)(hua)(hua)(hua)劑等,在(zai)加熱加壓下硫(liu)(liu)化(hua)(hua)(hua)(hua)成(cheng)彈(dan)性(xing)體。硅(gui)橡膠(jiao)(jiao)的(de)補強(qiang)主(zhu)要是(shi)各(ge)種(zhong)(zhong)類型的(de)白炭黑(hei),可使硫(liu)(liu)化(hua)(hua)(hua)(hua)膠(jiao)(jiao)的(de)強(qiang)度增加數十(shi)倍。有時為了(le)降低成(cheng)本或改善膠(jiao)(jiao)料性(xing)能及賦予硫(liu)(liu)化(hua)(hua)(hua)(hua)膠(jiao)(jiao)各(ge)種(zhong)(zhong)特殊的(de)性(xing)能,也加入(ru)相應的(de)各(ge)種(zhong)(zhong)添加劑。硫(liu)(liu)化(hua)(hua)(hua)(hua)劑是(shi)各(ge)種(zhong)(zhong)有機過(guo)氧(yang)(yang)化(hua)(hua)(hua)(hua)物或加成(cheng)反應催化(hua)(hua)(hua)(hua)劑。
加工成(cheng)型方法如(ru)圖所示。一(yi)次硫(liu)化(hua)的(de)(de)(de)目(mu)(mu)的(de)(de)(de)是進行高分子鏈的(de)(de)(de)交聯(lian)反應;二次硫(liu)化(hua)的(de)(de)(de)目(mu)(mu)的(de)(de)(de)是進行補(bu)充(chong)交聯(lian)、驅(qu)除硫(liu)化(hua)劑分解(jie)產物(wu)(wu)和其他揮發性化(hua)合物(wu)(wu)以(yi)穩定(ding)硫(liu)化(hua)膠的(de)(de)(de)各項性能。常用的(de)(de)(de)設備(bei)有開放式(shi)煉膠機(ji)(ji)、捏(nie)合機(ji)(ji)及真空密煉機(ji)(ji)。
主要性能
(1)高(gao)溫(wen)(wen)性(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)。硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)顯(xian)著的特征是(shi)(shi)高(gao)溫(wen)(wen)穩定(ding)性(xing)(xing)(xing)(xing)(xing),雖然常(chang)溫(wen)(wen)下(xia)(xia)硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)的強度僅是(shi)(shi)天然橡(xiang)(xiang)(xiang)膠(jiao)(jiao)或(huo)某些(xie)合(he)(he)成橡(xiang)(xiang)(xiang)膠(jiao)(jiao)的一(yi)半,但(dan)在200℃以上的高(gao)溫(wen)(wen)環境下(xia)(xia),硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)仍能(neng)(neng)(neng)保持一(yi)定(ding)的柔韌(ren)性(xing)(xing)(xing)(xing)(xing)、回彈性(xing)(xing)(xing)(xing)(xing)和表面硬度,且(qie)力學(xue)性(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)無明(ming)(ming)顯(xian)變化。(2)低(di)溫(wen)(wen)性(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)的玻(bo)璃化溫(wen)(wen)度一(yi)般為-70~-50℃,特殊配方可達(da)-100℃,表明(ming)(ming)其低(di)溫(wen)(wen)性(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)優(you)異。這對(dui)航空、宇航工業(ye)的意義(yi)重大。(3)耐(nai)候(hou)性(xing)(xing)(xing)(xing)(xing)硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)中Si-O-Si鍵對(dui)氧(yang)、臭氧(yang)及紫外(wai)線(xian)等(deng)十分(fen)穩定(ding),在不(bu)加任何添(tian)加劑(ji)(ji)的情況下(xia)(xia),就具有優(you)良的耐(nai)候(hou)性(xing)(xing)(xing)(xing)(xing)。(4)電(dian)氣(qi)(qi)性(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)。硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)具有優(you)異的絕(jue)緣(yuan)性(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng),耐(nai)電(dian)暈(yun)性(xing)(xing)(xing)(xing)(xing)和耐(nai)電(dian)弧性(xing)(xing)(xing)(xing)(xing)也非(fei)常(chang)好(hao)。(5)物理(li)機械性(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)。硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)常(chang)溫(wen)(wen)下(xia)(xia)的物理(li)機械性(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)比(bi)通用(yong)(yong)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)差,但(dan)在150℃的高(gao)溫(wen)(wen)和-50℃的低(di)溫(wen)(wen)下(xia)(xia),其物理(li)機械性(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)優(you)于(yu)通用(yong)(yong)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)。(6)耐(nai)油及化學(xue)試劑(ji)(ji)性(xing)(xing)(xing)(xing)(xing)。普(pu)通硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)具有中等(deng)的耐(nai)油、耐(nai)溶劑(ji)(ji)性(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)。(7)氣(qi)(qi)體(ti)透(tou)過性(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)。室(shi)溫(wen)(wen)下(xia)(xia)硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)對(dui)空氣(qi)(qi)、氮、氧(yang)、二氧(yang)化碳等(deng)氣(qi)(qi)體(ti)的透(tou)氣(qi)(qi)性(xing)(xing)(xing)(xing)(xing)比(bi)天然橡(xiang)(xiang)(xiang)膠(jiao)(jiao)高(gao)出30-50倍。(8)生理(li)惰(duo)性(xing)(xing)(xing)(xing)(xing)。硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)無毒,無味,無嗅,與(yu)人體(ti)組(zu)織(zhi)(zhi)不(bu)粘連,具有抗凝血作(zuo)用(yong)(yong),對(dui)肌體(ti)組(zu)織(zhi)(zhi)的反應性(xing)(xing)(xing)(xing)(xing)非(fei)常(chang)少。特別適(shi)合(he)(he)作(zuo)為醫用(yong)(yong)材料。
硅橡膠的用量
據(ju)中國(guo)汽(qi)(qi)(qi)車(che)(che)工(gong)業(ye)協會(hui)統(tong)計,2012年(nian)(nian),汽(qi)(qi)(qi)車(che)(che)產(chan)(chan)(chan)銷(xiao)分(fen)別(bie)達(da)到1927.18萬輛(liang)和(he)(he)1930.64萬輛(liang),同比分(fen)別(bie)增(zeng)長4.63%和(he)(he)4.33%,汽(qi)(qi)(qi)車(che)(che)工(gong)業(ye)硅橡(xiang)(xiang)膠(jiao)(jiao)的用(yong)量(liang)約達(da)2.0萬t。根據(ju)觀(guan)研天下(xia)的新研究,增(zeng)加有(you)(you)機硅材料在汽(qi)(qi)(qi)車(che)(che)零(ling)部件(jian)方面的用(yong)量(liang),可以(yi)大幅度提高汽(qi)(qi)(qi)車(che)(che)的安全性(xing)能(neng),因此(ci),汽(qi)(qi)(qi)車(che)(che)產(chan)(chan)(chan)量(liang)和(he)(he)單車(che)(che)用(yong)量(liang)水平的提高都將推動汽(qi)(qi)(qi)車(che)(che)工(gong)業(ye)對硅橡(xiang)(xiang)膠(jiao)(jiao)需求(qiu)的增(zeng)加。國(guo)家鼓勵自(zi)主(zhu)品牌(pai)(pai)(pai)的汽(qi)(qi)(qi)車(che)(che)發(fa)展,關鍵汽(qi)(qi)(qi)車(che)(che)零(ling)部件(jian)實現自(zi)主(zhu)化(hua),《2012年(nian)(nian)度黨政(zheng)機關公(gong)務(wu)用(yong)車(che)(che)選用(yong)車(che)(che)型目錄(征求(qiu)意(yi)見稿)》為自(zi)主(zhu)品牌(pai)(pai)(pai)擴大在政(zheng)府(fu)采購(gou)的市場份額,為改變目前國(guo)內政(zheng)府(fu)采購(gou)以(yi)合資品牌(pai)(pai)(pai)產(chan)(chan)(chan)品為主(zhu)的局面提供了(le)保障(zhang)。促進自(zi)主(zhu)品牌(pai)(pai)(pai)發(fa)展,國(guo)產(chan)(chan)(chan)汽(qi)(qi)(qi)車(che)(che)業(ye)的繁榮(rong)將為汽(qi)(qi)(qi)車(che)(che)膠(jiao)(jiao)的應(ying)用(yong)提供有(you)(you)力保障(zhang)。預測未(wei)來3年(nian)(nian),我國(guo)室溫硫化(hua)硅橡(xiang)(xiang)膠(jiao)(jiao)在汽(qi)(qi)(qi)車(che)(che)行(xing)業(ye)將以(yi)年(nian)(nian)均(jun)20%增(zeng)長。
此外,硅(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)是重(zhong)要(yao)的(de)(de)非(fei)石(shi)油(you)基(ji)(ji)合(he)成橡(xiang)(xiang)膠(jiao)(jiao)(jiao),約占非(fei)石(shi)油(you)基(ji)(ji)合(he)成橡(xiang)(xiang)膠(jiao)(jiao)(jiao)消費量的(de)(de)98%。但因為(wei)(wei)石(shi)油(you)價(jia)格(ge)的(de)(de)大(da)幅(fu)上漲(zhang),同時我國(guo)在硅(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)的(de)(de)關鍵(jian)原(yuan)(yuan)料有機硅(gui)(gui)(gui)單體(ti)的(de)(de)生產(chan)技(ji)術(shu)(shu)方面(mian)取(qu)得突(tu)破,有機硅(gui)(gui)(gui)單體(ti)的(de)(de)生產(chan)技(ji)術(shu)(shu)在2005年(nian)前被幾(ji)家跨(kua)國(guo)公司(si)壟斷,但目前我國(guo)已發展成為(wei)(wei)全球有機硅(gui)(gui)(gui)單體(ti)第1大(da)國(guo),這(zhe)2個方面(mian)原(yuan)(yuan)因使硅(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)的(de)(de)價(jia)格(ge)從2011年(nian)起開始(shi)低于石(shi)油(you)基(ji)(ji)合(he)成橡(xiang)(xiang)膠(jiao)(jiao)(jiao),僅約為(wei)(wei)大(da)宗(zong)石(shi)油(you)基(ji)(ji)橡(xiang)(xiang)膠(jiao)(jiao)(jiao)的(de)(de)80%~90%,成為(wei)(wei)廉(lian)價(jia)的(de)(de)合(he)成橡(xiang)(xiang)膠(jiao)(jiao)(jiao),并開始(shi)大(da)規模替代石(shi)油(you)基(ji)(ji)合(he)成橡(xiang)(xiang)膠(jiao)(jiao)(jiao)。這(zhe)將極大(da)拓展有機硅(gui)(gui)(gui)產(chan)業的(de)(de)市場空間,同時將帶動硅(gui)(gui)(gui)油(you)、硅(gui)(gui)(gui)烷偶聯劑和硅(gui)(gui)(gui)樹(shu)脂(zhi)等(deng)其他有機硅(gui)(gui)(gui)產(chan)品的(de)(de)消費。