
硅橡膠是指主(zhu)鏈由硅(gui)(gui)和氧原(yuan)子(zi)交替構成(cheng)(cheng),硅(gui)(gui)原(yuan)子(zi)上通常連(lian)有兩個有機基(ji)團的(de)(de)橡(xiang)膠(jiao)(jiao)。普(pu)通的(de)(de)硅(gui)(gui)橡(xiang)膠(jiao)(jiao)主(zhu)要由含甲(jia)基(ji)和少量(liang)乙烯基(ji)的(de)(de)硅(gui)(gui)氧鏈節(jie)組成(cheng)(cheng)。苯(ben)基(ji)的(de)(de)引(yin)入可提(ti)高硅(gui)(gui)橡(xiang)膠(jiao)(jiao)的(de)(de)耐(nai)高、低(di)溫(wen)性(xing)(xing)能(neng)(neng)(neng),三氟丙基(ji)及氰(qing)基(ji)的(de)(de)引(yin)入則(ze)可提(ti)高硅(gui)(gui)橡(xiang)膠(jiao)(jiao)的(de)(de)耐(nai)溫(wen)及耐(nai)油性(xing)(xing)能(neng)(neng)(neng)。硅(gui)(gui)橡(xiang)膠(jiao)(jiao)耐(nai)低(di)溫(wen)性(xing)(xing)能(neng)(neng)(neng)良好(hao)(hao),一般在-55℃下仍能(neng)(neng)(neng)工(gong)作(zuo)。引(yin)入苯(ben)基(ji)后,可達-73℃。硅(gui)(gui)橡(xiang)膠(jiao)(jiao)的(de)(de)耐(nai)熱性(xing)(xing)能(neng)(neng)(neng)也(ye)很突出,在180℃下可長(chang)期工(gong)作(zuo),稍高于200℃也(ye)能(neng)(neng)(neng)承受數周或(huo)更長(chang)時(shi)間仍有彈性(xing)(xing),瞬時(shi)可耐(nai)300℃以(yi)上的(de)(de)高溫(wen)。硅(gui)(gui)橡(xiang)膠(jiao)(jiao)的(de)(de)透氣性(xing)(xing)好(hao)(hao),氧氣透過率在合成(cheng)(cheng)聚合物(wu)中是較高的(de)(de)。此(ci)外,硅(gui)(gui)橡(xiang)膠(jiao)(jiao)還具有生理惰性(xing)(xing)、不會導致(zhi)凝血(xue)的(de)(de)突出特性(xing)(xing),因此(ci)在醫用(yong)領域應用(yong)廣(guang)泛。
主要品種
硅(gui)(gui)橡(xiang)膠(jiao)分(fen)類的(de)方法(fa)很多,通常(chang)按(an)固化(hua)前的(de)形態分(fen)為固體(ti)(ti)硅(gui)(gui)橡(xiang)膠(jiao)和(he)液體(ti)(ti)硅(gui)(gui)橡(xiang)膠(jiao);按(an)硫(liu)(liu)化(hua)溫(wen)度分(fen)為室溫(wen)硫(liu)(liu)化(hua)硅(gui)(gui)橡(xiang)膠(jiao),高(gao)溫(wen)硫(liu)(liu)化(hua)硅(gui)(gui)橡(xiang)膠(jiao);按(an)所(suo)用(yong)(yong)單體(ti)(ti)的(de)不(bu)同(tong),可分(fen)為甲基(ji)(ji)乙烯基(ji)(ji)硅(gui)(gui)橡(xiang)膠(jiao),甲基(ji)(ji)苯(ben)基(ji)(ji)乙烯基(ji)(ji)硅(gui)(gui)橡(xiang)膠(jiao)、氟(fu)硅(gui)(gui),腈硅(gui)(gui)橡(xiang)膠(jiao)等(deng);按(an)性(xing)能和(he)用(yong)(yong)途的(de)不(bu)同(tong)又可分(fen)為通用(yong)(yong)型(xing)(xing)(xing)、超(chao)耐低溫(wen)型(xing)(xing)(xing)、超(chao)耐高(gao)溫(wen)型(xing)(xing)(xing)、高(gao)強力型(xing)(xing)(xing)、耐油型(xing)(xing)(xing)、醫用(yong)(yong)型(xing)(xing)(xing)等(deng)等(deng)。
發展史
硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)早期是由(you)美(mei)國以三氯(lv)化鐵為催化劑(ji)合成的。1945年(nian),硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)產(chan)品問世(shi)。1948年(nian),采(cai)用高(gao)比(bi)表面積(ji)的氣相法(fa)白(bai)炭黑(hei)補強的硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)研(yan)(yan)(yan)制成功,使硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)的性能(neng)躍升到實用階段,奠定了現代硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)生(sheng)產(chan)技(ji)術(shu)的基(ji)(ji)礎。從二(er)甲基(ji)(ji)二(er)氯(lv)硅(gui)(gui)(gui)烷(wan)合成開始生(sheng)產(chan)硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)的國家(jia)有美(mei)國。俄羅斯、德國、日(ri)本(ben)、韓國和(he)中(zhong)(zhong)國等(deng)。中(zhong)(zhong)國硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)的工業化研(yan)(yan)(yan)究(jiu)(jiu)始于1957年(nian),多家(jia)研(yan)(yan)(yan)究(jiu)(jiu)所(suo)和(he)企業陸續開發出各(ge)種硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)。到2003年(nian)底,中(zhong)(zhong)國硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(jiao)生(sheng)產(chan)能(neng)力為135千(qian)噸,其(qi)中(zhong)(zhong)高(gao)溫膠(jiao)(jiao)(jiao)(jiao)100千(qian)噸。
高溫硫化硅橡膠
高(gao)(gao)溫(wen)硫(liu)化(hua)(hua)(hua)硅(gui)橡膠(jiao)是指聚硅(gui)氧烷變成(cheng)(cheng)彈性(xing)體的(de)過程(cheng)是經過高(gao)(gao)溫(wen)(110-170℃)硫(liu)化(hua)(hua)(hua)成(cheng)(cheng)型(xing)的(de)。它主要(yao)以高(gao)(gao)分子量的(de)聚甲基(ji)乙(yi)烯基(ji)硅(gui)氧烷為生膠(jiao),混(hun)入補強(qiang)填料、硫(liu)化(hua)(hua)(hua)劑等,在加(jia)(jia)(jia)熱加(jia)(jia)(jia)壓下硫(liu)化(hua)(hua)(hua)成(cheng)(cheng)彈性(xing)體。硅(gui)橡膠(jiao)的(de)補強(qiang)主要(yao)是各(ge)(ge)種類型(xing)的(de)白(bai)炭黑,可使(shi)硫(liu)化(hua)(hua)(hua)膠(jiao)的(de)強(qiang)度增加(jia)(jia)(jia)數十倍。有(you)時為了降低(di)成(cheng)(cheng)本或改善膠(jiao)料性(xing)能及賦(fu)予硫(liu)化(hua)(hua)(hua)膠(jiao)各(ge)(ge)種特(te)殊(shu)的(de)性(xing)能,也加(jia)(jia)(jia)入相應的(de)各(ge)(ge)種添加(jia)(jia)(jia)劑。硫(liu)化(hua)(hua)(hua)劑是各(ge)(ge)種有(you)機過氧化(hua)(hua)(hua)物(wu)或加(jia)(jia)(jia)成(cheng)(cheng)反應催化(hua)(hua)(hua)劑。
加工成型方法如圖(tu)所(suo)示。一次硫化(hua)的(de)(de)(de)(de)(de)目的(de)(de)(de)(de)(de)是(shi)進(jin)行高分(fen)子鏈的(de)(de)(de)(de)(de)交聯反應;二次硫化(hua)的(de)(de)(de)(de)(de)目的(de)(de)(de)(de)(de)是(shi)進(jin)行補充(chong)交聯、驅除硫化(hua)劑分(fen)解產物和其他揮(hui)發性化(hua)合(he)(he)物以穩定硫化(hua)膠(jiao)的(de)(de)(de)(de)(de)各項(xiang)性能(neng)。常用的(de)(de)(de)(de)(de)設備有(you)開放式煉膠(jiao)機(ji)、捏合(he)(he)機(ji)及(ji)真空(kong)密煉機(ji)。
主要性能
(1)高(gao)溫(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)。硅(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)顯著(zhu)的(de)特征是(shi)高(gao)溫(wen)(wen)穩定性(xing)(xing)(xing)(xing)(xing)(xing)(xing),雖(sui)然常溫(wen)(wen)下硅(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)的(de)強度(du)僅是(shi)天(tian)然橡(xiang)(xiang)(xiang)(xiang)膠(jiao)或(huo)某些合成橡(xiang)(xiang)(xiang)(xiang)膠(jiao)的(de)一(yi)半,但在(zai)200℃以上的(de)高(gao)溫(wen)(wen)環境(jing)下,硅(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)仍能(neng)(neng)保持(chi)一(yi)定的(de)柔韌性(xing)(xing)(xing)(xing)(xing)(xing)(xing)、回彈性(xing)(xing)(xing)(xing)(xing)(xing)(xing)和(he)表面硬度(du),且力學性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)無明(ming)顯變化(hua)。(2)低溫(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)硅(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)的(de)玻(bo)璃(li)化(hua)溫(wen)(wen)度(du)一(yi)般為-70~-50℃,特殊配方(fang)可達-100℃,表明(ming)其(qi)低溫(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)優異。這對(dui)(dui)航(hang)空、宇航(hang)工業(ye)的(de)意義重大。(3)耐(nai)候(hou)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)硅(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)中Si-O-Si鍵(jian)對(dui)(dui)氧、臭氧及紫(zi)外線等十分(fen)穩定,在(zai)不加任何添加劑的(de)情況(kuang)下,就(jiu)具有優良(liang)的(de)耐(nai)候(hou)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)。(4)電(dian)氣(qi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)。硅(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)具有優異的(de)絕緣(yuan)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng),耐(nai)電(dian)暈(yun)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)和(he)耐(nai)電(dian)弧(hu)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)也(ye)非常好。(5)物(wu)理機械(xie)(xie)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)。硅(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)常溫(wen)(wen)下的(de)物(wu)理機械(xie)(xie)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)比通用(yong)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)差,但在(zai)150℃的(de)高(gao)溫(wen)(wen)和(he)-50℃的(de)低溫(wen)(wen)下,其(qi)物(wu)理機械(xie)(xie)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)優于通用(yong)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)。(6)耐(nai)油及化(hua)學試(shi)劑性(xing)(xing)(xing)(xing)(xing)(xing)(xing)。普通硅(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)具有中等的(de)耐(nai)油、耐(nai)溶劑性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)。(7)氣(qi)體(ti)透過性(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)。室溫(wen)(wen)下硅(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)對(dui)(dui)空氣(qi)、氮(dan)、氧、二氧化(hua)碳等氣(qi)體(ti)的(de)透氣(qi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)比天(tian)然橡(xiang)(xiang)(xiang)(xiang)膠(jiao)高(gao)出30-50倍。(8)生理惰(duo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)。硅(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)無毒(du),無味,無嗅,與人體(ti)組織(zhi)不粘連,具有抗凝血作用(yong),對(dui)(dui)肌體(ti)組織(zhi)的(de)反應性(xing)(xing)(xing)(xing)(xing)(xing)(xing)非常少。特別(bie)適合作為醫用(yong)材料。
硅橡膠的用量
據中國(guo)(guo)汽(qi)(qi)(qi)(qi)車(che)(che)工業(ye)協會統計(ji),2012年(nian),汽(qi)(qi)(qi)(qi)車(che)(che)產銷(xiao)分別達到1927.18萬(wan)輛和(he)1930.64萬(wan)輛,同(tong)比(bi)分別增長4.63%和(he)4.33%,汽(qi)(qi)(qi)(qi)車(che)(che)工業(ye)硅(gui)(gui)橡膠(jiao)(jiao)的(de)用(yong)(yong)(yong)量約達2.0萬(wan)t。根據觀研天下的(de)新研究,增加有(you)機(ji)硅(gui)(gui)材料在(zai)汽(qi)(qi)(qi)(qi)車(che)(che)零(ling)部(bu)件方面(mian)的(de)用(yong)(yong)(yong)量,可以(yi)大幅(fu)度(du)提高汽(qi)(qi)(qi)(qi)車(che)(che)的(de)安(an)全性能,因此,汽(qi)(qi)(qi)(qi)車(che)(che)產量和(he)單車(che)(che)用(yong)(yong)(yong)量水(shui)平的(de)提高都將(jiang)(jiang)推動汽(qi)(qi)(qi)(qi)車(che)(che)工業(ye)對硅(gui)(gui)橡膠(jiao)(jiao)需求的(de)增加。國(guo)(guo)家(jia)鼓勵自(zi)主品(pin)牌的(de)汽(qi)(qi)(qi)(qi)車(che)(che)發(fa)展,關(guan)鍵汽(qi)(qi)(qi)(qi)車(che)(che)零(ling)部(bu)件實現自(zi)主化,《2012年(nian)度(du)黨政(zheng)機(ji)關(guan)公務用(yong)(yong)(yong)車(che)(che)選用(yong)(yong)(yong)車(che)(che)型(xing)目(mu)錄(征求意見稿(gao))》為(wei)自(zi)主品(pin)牌擴大在(zai)政(zheng)府(fu)采購的(de)市場份額(e),為(wei)改變目(mu)前國(guo)(guo)內政(zheng)府(fu)采購以(yi)合資(zi)品(pin)牌產品(pin)為(wei)主的(de)局面(mian)提供(gong)(gong)了保障。促進(jin)自(zi)主品(pin)牌發(fa)展,國(guo)(guo)產汽(qi)(qi)(qi)(qi)車(che)(che)業(ye)的(de)繁(fan)榮將(jiang)(jiang)為(wei)汽(qi)(qi)(qi)(qi)車(che)(che)膠(jiao)(jiao)的(de)應用(yong)(yong)(yong)提供(gong)(gong)有(you)力保障。預(yu)測未來(lai)3年(nian),我國(guo)(guo)室溫(wen)硫化硅(gui)(gui)橡膠(jiao)(jiao)在(zai)汽(qi)(qi)(qi)(qi)車(che)(che)行業(ye)將(jiang)(jiang)以(yi)年(nian)均(jun)20%增長。
此外,硅(gui)(gui)橡(xiang)(xiang)膠(jiao)是重要的(de)(de)非石(shi)油(you)基合(he)(he)成(cheng)(cheng)(cheng)(cheng)(cheng)橡(xiang)(xiang)膠(jiao),約(yue)占非石(shi)油(you)基合(he)(he)成(cheng)(cheng)(cheng)(cheng)(cheng)橡(xiang)(xiang)膠(jiao)消費量的(de)(de)98%。但因為石(shi)油(you)價(jia)格(ge)的(de)(de)大(da)(da)幅上(shang)漲,同(tong)時(shi)我(wo)國(guo)(guo)在硅(gui)(gui)橡(xiang)(xiang)膠(jiao)的(de)(de)關(guan)鍵原料(liao)有機(ji)(ji)硅(gui)(gui)單(dan)(dan)體(ti)(ti)的(de)(de)生(sheng)(sheng)產(chan)技術(shu)方面(mian)取得突(tu)破,有機(ji)(ji)硅(gui)(gui)單(dan)(dan)體(ti)(ti)的(de)(de)生(sheng)(sheng)產(chan)技術(shu)在2005年(nian)前被幾家跨國(guo)(guo)公司壟斷,但目(mu)前我(wo)國(guo)(guo)已發展成(cheng)(cheng)(cheng)(cheng)(cheng)為全(quan)球有機(ji)(ji)硅(gui)(gui)單(dan)(dan)體(ti)(ti)第(di)1大(da)(da)國(guo)(guo),這2個方面(mian)原因使硅(gui)(gui)橡(xiang)(xiang)膠(jiao)的(de)(de)價(jia)格(ge)從2011年(nian)起開始(shi)低于石(shi)油(you)基合(he)(he)成(cheng)(cheng)(cheng)(cheng)(cheng)橡(xiang)(xiang)膠(jiao),僅約(yue)為大(da)(da)宗石(shi)油(you)基橡(xiang)(xiang)膠(jiao)的(de)(de)80%~90%,成(cheng)(cheng)(cheng)(cheng)(cheng)為廉價(jia)的(de)(de)合(he)(he)成(cheng)(cheng)(cheng)(cheng)(cheng)橡(xiang)(xiang)膠(jiao),并開始(shi)大(da)(da)規模替代石(shi)油(you)基合(he)(he)成(cheng)(cheng)(cheng)(cheng)(cheng)橡(xiang)(xiang)膠(jiao)。這將極大(da)(da)拓展有機(ji)(ji)硅(gui)(gui)產(chan)業(ye)的(de)(de)市場空間(jian),同(tong)時(shi)將帶(dai)動硅(gui)(gui)油(you)、硅(gui)(gui)烷偶聯劑和(he)硅(gui)(gui)樹脂(zhi)等其他有機(ji)(ji)硅(gui)(gui)產(chan)品的(de)(de)消費。