
硅橡膠是指主(zhu)鏈由(you)(you)硅(gui)(gui)(gui)和氧原(yuan)子(zi)交替構成,硅(gui)(gui)(gui)原(yuan)子(zi)上通常連有兩(liang)個有機基(ji)團的(de)(de)橡(xiang)膠(jiao)(jiao)(jiao)。普通的(de)(de)硅(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao)主(zhu)要由(you)(you)含(han)甲(jia)基(ji)和少量乙烯基(ji)的(de)(de)硅(gui)(gui)(gui)氧鏈節組成。苯基(ji)的(de)(de)引(yin)入(ru)可(ke)提高(gao)硅(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao)的(de)(de)耐高(gao)、低溫(wen)(wen)(wen)性(xing)能(neng)(neng),三氟丙基(ji)及氰(qing)基(ji)的(de)(de)引(yin)入(ru)則(ze)可(ke)提高(gao)硅(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao)的(de)(de)耐溫(wen)(wen)(wen)及耐油性(xing)能(neng)(neng)。硅(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao)耐低溫(wen)(wen)(wen)性(xing)能(neng)(neng)良好,一般在(zai)(zai)-55℃下仍能(neng)(neng)工(gong)作(zuo)。引(yin)入(ru)苯基(ji)后,可(ke)達-73℃。硅(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao)的(de)(de)耐熱性(xing)能(neng)(neng)也很突出,在(zai)(zai)180℃下可(ke)長期工(gong)作(zuo),稍高(gao)于200℃也能(neng)(neng)承受數周或更長時(shi)間仍有彈性(xing),瞬時(shi)可(ke)耐300℃以上的(de)(de)高(gao)溫(wen)(wen)(wen)。硅(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao)的(de)(de)透氣性(xing)好,氧氣透過率在(zai)(zai)合成聚合物中是較高(gao)的(de)(de)。此外,硅(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao)還具有生理惰(duo)性(xing)、不會導致凝血的(de)(de)突出特性(xing),因(yin)此在(zai)(zai)醫用領域應用廣(guang)泛。
主要品種
硅(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao)分類的方(fang)法很多(duo),通常按(an)固化前的形態(tai)分為固體(ti)硅(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao)和(he)液體(ti)硅(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao);按(an)硫化溫度(du)分為室溫硫化硅(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao),高溫硫化硅(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao);按(an)所用單體(ti)的不(bu)同(tong),可分為甲基(ji)乙烯(xi)基(ji)硅(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao),甲基(ji)苯(ben)基(ji)乙烯(xi)基(ji)硅(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao)、氟硅(gui)(gui),腈硅(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao)等(deng);按(an)性能(neng)和(he)用途的不(bu)同(tong)又(you)可分為通用型(xing)(xing)(xing)、超耐(nai)低溫型(xing)(xing)(xing)、超耐(nai)高溫型(xing)(xing)(xing)、高強(qiang)力(li)型(xing)(xing)(xing)、耐(nai)油型(xing)(xing)(xing)、醫用型(xing)(xing)(xing)等(deng)等(deng)。
發展史
硅(gui)橡(xiang)膠(jiao)(jiao)(jiao)早(zao)期是由美國以(yi)三氯(lv)化(hua)(hua)鐵為(wei)催化(hua)(hua)劑(ji)合(he)成的(de)。1945年(nian),硅(gui)橡(xiang)膠(jiao)(jiao)(jiao)產品問(wen)世。1948年(nian),采用高比表面積的(de)氣相法(fa)白炭黑補強的(de)硅(gui)橡(xiang)膠(jiao)(jiao)(jiao)研制成功,使硅(gui)橡(xiang)膠(jiao)(jiao)(jiao)的(de)性能(neng)躍升到實用階段(duan),奠(dian)定了現代硅(gui)橡(xiang)膠(jiao)(jiao)(jiao)生(sheng)產技(ji)術(shu)的(de)基礎。從(cong)二甲基二氯(lv)硅(gui)烷(wan)合(he)成開(kai)始生(sheng)產硅(gui)橡(xiang)膠(jiao)(jiao)(jiao)的(de)國家(jia)有美國。俄羅斯(si)、德(de)國、日本、韓國和(he)中(zhong)(zhong)(zhong)國等。中(zhong)(zhong)(zhong)國硅(gui)橡(xiang)膠(jiao)(jiao)(jiao)的(de)工業(ye)化(hua)(hua)研究始于1957年(nian),多家(jia)研究所(suo)和(he)企業(ye)陸(lu)續開(kai)發出各種硅(gui)橡(xiang)膠(jiao)(jiao)(jiao)。到2003年(nian)底,中(zhong)(zhong)(zhong)國硅(gui)橡(xiang)膠(jiao)(jiao)(jiao)生(sheng)產能(neng)力為(wei)135千噸,其(qi)中(zhong)(zhong)(zhong)高溫膠(jiao)(jiao)(jiao)100千噸。
高溫硫化硅橡膠
高溫(wen)硫(liu)(liu)化(hua)(hua)(hua)硅(gui)橡(xiang)膠(jiao)(jiao)是指(zhi)聚硅(gui)氧(yang)烷變成彈性(xing)體(ti)的(de)(de)過程(cheng)是經過高溫(wen)(110-170℃)硫(liu)(liu)化(hua)(hua)(hua)成型(xing)的(de)(de)。它主要以高分子量(liang)的(de)(de)聚甲基乙烯基硅(gui)氧(yang)烷為(wei)生膠(jiao)(jiao),混入補(bu)強填料、硫(liu)(liu)化(hua)(hua)(hua)劑等,在(zai)加(jia)熱加(jia)壓下硫(liu)(liu)化(hua)(hua)(hua)成彈性(xing)體(ti)。硅(gui)橡(xiang)膠(jiao)(jiao)的(de)(de)補(bu)強主要是各(ge)種類型(xing)的(de)(de)白炭黑,可(ke)使(shi)硫(liu)(liu)化(hua)(hua)(hua)膠(jiao)(jiao)的(de)(de)強度(du)增加(jia)數十倍。有(you)時(shi)為(wei)了(le)降低(di)成本或(huo)改善膠(jiao)(jiao)料性(xing)能(neng)及賦予硫(liu)(liu)化(hua)(hua)(hua)膠(jiao)(jiao)各(ge)種特殊的(de)(de)性(xing)能(neng),也加(jia)入相應的(de)(de)各(ge)種添加(jia)劑。硫(liu)(liu)化(hua)(hua)(hua)劑是各(ge)種有(you)機(ji)過氧(yang)化(hua)(hua)(hua)物(wu)或(huo)加(jia)成反應催化(hua)(hua)(hua)劑。
加工成型(xing)方法如圖所示。一次(ci)硫化(hua)(hua)的(de)(de)(de)目的(de)(de)(de)是(shi)(shi)進行高分子鏈的(de)(de)(de)交聯反應;二次(ci)硫化(hua)(hua)的(de)(de)(de)目的(de)(de)(de)是(shi)(shi)進行補(bu)充交聯、驅除硫化(hua)(hua)劑分解(jie)產(chan)物和(he)其他揮發性化(hua)(hua)合物以穩定(ding)硫化(hua)(hua)膠的(de)(de)(de)各項性能。常用(yong)的(de)(de)(de)設備(bei)有開放式(shi)煉(lian)膠機、捏合機及真空(kong)密煉(lian)機。
主要性能
(1)高(gao)溫(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)。硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)顯著的(de)(de)(de)(de)特征(zheng)是高(gao)溫(wen)(wen)穩(wen)定(ding)(ding)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing),雖然常(chang)溫(wen)(wen)下(xia)硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)的(de)(de)(de)(de)強度(du)僅是天然橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)或某些合成(cheng)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)的(de)(de)(de)(de)一(yi)半,但在200℃以上的(de)(de)(de)(de)高(gao)溫(wen)(wen)環(huan)境下(xia),硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)仍能(neng)(neng)(neng)保持一(yi)定(ding)(ding)的(de)(de)(de)(de)柔韌性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)、回彈性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)和(he)表面硬(ying)度(du),且力學(xue)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)無(wu)明(ming)顯變化。(2)低(di)溫(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)的(de)(de)(de)(de)玻(bo)璃(li)化溫(wen)(wen)度(du)一(yi)般為(wei)-70~-50℃,特殊配方可(ke)達(da)-100℃,表明(ming)其(qi)低(di)溫(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)優(you)異(yi)。這對航(hang)空、宇航(hang)工業的(de)(de)(de)(de)意義重大(da)。(3)耐(nai)候(hou)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)中Si-O-Si鍵對氧(yang)、臭氧(yang)及紫外線等十(shi)分穩(wen)定(ding)(ding),在不加(jia)任何(he)添加(jia)劑(ji)的(de)(de)(de)(de)情(qing)況(kuang)下(xia),就具(ju)(ju)有(you)優(you)良的(de)(de)(de)(de)耐(nai)候(hou)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)。(4)電氣(qi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)。硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)具(ju)(ju)有(you)優(you)異(yi)的(de)(de)(de)(de)絕(jue)緣性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng),耐(nai)電暈性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)和(he)耐(nai)電弧(hu)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)也非常(chang)好。(5)物理機(ji)械(xie)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)。硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)常(chang)溫(wen)(wen)下(xia)的(de)(de)(de)(de)物理機(ji)械(xie)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)比通(tong)用橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)差(cha),但在150℃的(de)(de)(de)(de)高(gao)溫(wen)(wen)和(he)-50℃的(de)(de)(de)(de)低(di)溫(wen)(wen)下(xia),其(qi)物理機(ji)械(xie)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)優(you)于通(tong)用橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)。(6)耐(nai)油及化學(xue)試劑(ji)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)。普通(tong)硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)具(ju)(ju)有(you)中等的(de)(de)(de)(de)耐(nai)油、耐(nai)溶劑(ji)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)。(7)氣(qi)體(ti)(ti)透過性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)。室溫(wen)(wen)下(xia)硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)對空氣(qi)、氮(dan)、氧(yang)、二(er)氧(yang)化碳等氣(qi)體(ti)(ti)的(de)(de)(de)(de)透氣(qi)性(xing)(xing)(xing)(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。(8)生理惰性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)。硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)無(wu)毒,無(wu)味,無(wu)嗅(xiu),與人體(ti)(ti)組(zu)織(zhi)不粘連,具(ju)(ju)有(you)抗凝(ning)血作用,對肌體(ti)(ti)組(zu)織(zhi)的(de)(de)(de)(de)反應性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)非常(chang)少。特別適合作為(wei)醫用材料。
硅橡膠的用量
據(ju)中國(guo)(guo)汽(qi)(qi)(qi)(qi)車(che)工(gong)業(ye)協(xie)會統計,2012年,汽(qi)(qi)(qi)(qi)車(che)產銷分別達到1927.18萬(wan)(wan)(wan)輛和1930.64萬(wan)(wan)(wan)輛,同比分別增長4.63%和4.33%,汽(qi)(qi)(qi)(qi)車(che)工(gong)業(ye)硅橡膠(jiao)的(de)(de)用量約(yue)達2.0萬(wan)(wan)(wan)t。根據(ju)觀研(yan)天下的(de)(de)新(xin)研(yan)究,增加(jia)有機硅材料在汽(qi)(qi)(qi)(qi)車(che)零部件方(fang)面的(de)(de)用量,可以大幅度(du)提高(gao)汽(qi)(qi)(qi)(qi)車(che)的(de)(de)安全性(xing)能,因此,汽(qi)(qi)(qi)(qi)車(che)產量和單車(che)用量水平的(de)(de)提高(gao)都將推動汽(qi)(qi)(qi)(qi)車(che)工(gong)業(ye)對硅橡膠(jiao)需求的(de)(de)增加(jia)。國(guo)(guo)家鼓(gu)勵自(zi)主品(pin)牌的(de)(de)汽(qi)(qi)(qi)(qi)車(che)發展,關鍵(jian)汽(qi)(qi)(qi)(qi)車(che)零部件實現自(zi)主化,《2012年度(du)黨政(zheng)機關公(gong)務用車(che)選用車(che)型目(mu)錄(征求意(yi)見稿)》為自(zi)主品(pin)牌擴大在政(zheng)府采(cai)購的(de)(de)市場份額,為改變目(mu)前國(guo)(guo)內政(zheng)府采(cai)購以合資品(pin)牌產品(pin)為主的(de)(de)局面提供了保(bao)障。促進(jin)自(zi)主品(pin)牌發展,國(guo)(guo)產汽(qi)(qi)(qi)(qi)車(che)業(ye)的(de)(de)繁榮(rong)將為汽(qi)(qi)(qi)(qi)車(che)膠(jiao)的(de)(de)應用提供有力保(bao)障。預測未來(lai)3年,我國(guo)(guo)室溫硫化硅橡膠(jiao)在汽(qi)(qi)(qi)(qi)車(che)行(xing)業(ye)將以年均20%增長。
此外,硅橡(xiang)膠(jiao)(jiao)是重(zhong)要(yao)的(de)非(fei)石油(you)基(ji)合(he)成(cheng)橡(xiang)膠(jiao)(jiao),約(yue)占非(fei)石油(you)基(ji)合(he)成(cheng)橡(xiang)膠(jiao)(jiao)消(xiao)費(fei)量的(de)98%。但(dan)因為石油(you)價格(ge)的(de)大(da)幅(fu)上漲,同時我國在硅橡(xiang)膠(jiao)(jiao)的(de)關鍵原料有(you)機(ji)硅單(dan)(dan)體(ti)(ti)的(de)生產(chan)技術方(fang)面(mian)取得突破,有(you)機(ji)硅單(dan)(dan)體(ti)(ti)的(de)生產(chan)技術在2005年前(qian)被幾家(jia)跨國公司壟(long)斷,但(dan)目前(qian)我國已發展成(cheng)為全球有(you)機(ji)硅單(dan)(dan)體(ti)(ti)第1大(da)國,這2個方(fang)面(mian)原因使硅橡(xiang)膠(jiao)(jiao)的(de)價格(ge)從2011年起開始低于石油(you)基(ji)合(he)成(cheng)橡(xiang)膠(jiao)(jiao),僅(jin)約(yue)為大(da)宗石油(you)基(ji)橡(xiang)膠(jiao)(jiao)的(de)80%~90%,成(cheng)為廉價的(de)合(he)成(cheng)橡(xiang)膠(jiao)(jiao),并開始大(da)規模替代(dai)石油(you)基(ji)合(he)成(cheng)橡(xiang)膠(jiao)(jiao)。這將極大(da)拓展有(you)機(ji)硅產(chan)業(ye)的(de)市場(chang)空(kong)間,同時將帶動硅油(you)、硅烷(wan)偶聯劑和硅樹脂等其他有(you)機(ji)硅產(chan)品的(de)消(xiao)費(fei)。