硅橡膠是指主鏈由(you)硅(gui)和氧原(yuan)子交替構成(cheng),硅(gui)原(yuan)子上(shang)通(tong)常(chang)連有(you)兩個有(you)機(ji)基(ji)(ji)團的(de)(de)(de)(de)橡(xiang)膠(jiao)。普通(tong)的(de)(de)(de)(de)硅(gui)橡(xiang)膠(jiao)主要由(you)含甲(jia)基(ji)(ji)和少量乙烯基(ji)(ji)的(de)(de)(de)(de)硅(gui)氧鏈節組成(cheng)。苯基(ji)(ji)的(de)(de)(de)(de)引入可提高(gao)硅(gui)橡(xiang)膠(jiao)的(de)(de)(de)(de)耐(nai)高(gao)、低溫(wen)性(xing)(xing)能(neng)(neng),三氟丙基(ji)(ji)及氰(qing)基(ji)(ji)的(de)(de)(de)(de)引入則(ze)可提高(gao)硅(gui)橡(xiang)膠(jiao)的(de)(de)(de)(de)耐(nai)溫(wen)及耐(nai)油性(xing)(xing)能(neng)(neng)。硅(gui)橡(xiang)膠(jiao)耐(nai)低溫(wen)性(xing)(xing)能(neng)(neng)良好,一般在(zai)-55℃下(xia)仍(reng)能(neng)(neng)工作(zuo)。引入苯基(ji)(ji)后,可達-73℃。硅(gui)橡(xiang)膠(jiao)的(de)(de)(de)(de)耐(nai)熱性(xing)(xing)能(neng)(neng)也很突出(chu),在(zai)180℃下(xia)可長(chang)期(qi)工作(zuo),稍(shao)高(gao)于200℃也能(neng)(neng)承受(shou)數周(zhou)或更長(chang)時間仍(reng)有(you)彈(dan)性(xing)(xing),瞬(shun)時可耐(nai)300℃以上(shang)的(de)(de)(de)(de)高(gao)溫(wen)。硅(gui)橡(xiang)膠(jiao)的(de)(de)(de)(de)透氣(qi)性(xing)(xing)好,氧氣(qi)透過率在(zai)合成(cheng)聚合物中是較(jiao)高(gao)的(de)(de)(de)(de)。此(ci)外,硅(gui)橡(xiang)膠(jiao)還具有(you)生理惰(duo)性(xing)(xing)、不會導致(zhi)凝血的(de)(de)(de)(de)突出(chu)特(te)性(xing)(xing),因此(ci)在(zai)醫用(yong)領域(yu)應用(yong)廣泛。
主要品(pin)種(zhong)
硅橡(xiang)膠分類的方法很多,通常按固化
前(qian)的形態分(fen)為(wei)固體(ti)硅(gui)(gui)橡膠和液體(ti)硅(gui)(gui)橡膠;按(an)硫化溫度分(fen)為(wei)室溫硫化硅(gui)(gui)橡膠,高溫硫化硅(gui)(gui)橡膠;按(an)所用(yong)單體(ti)的不(bu)同,可(ke)分(fen)為(wei)甲(jia)基(ji)(ji)乙烯基(ji)(ji)硅(gui)(gui)橡膠,甲(jia)基(ji)(ji)苯基(ji)(ji)乙烯基(ji)(ji)硅(gui)(gui)橡膠、氟硅(gui)(gui),腈硅(gui)(gui)橡膠等;按(an)性(xing)能和用(yong)途的不(bu)同又可(ke)分(fen)為(wei)通用(yong)型(xing)、超(chao)(chao)耐低溫型(xing)、超(chao)(chao)耐高溫型(xing)、高強力型(xing)、耐油型(xing)、醫(yi)用(yong)型(xing)等等。
發展史
硅(gui)(gui)橡(xiang)(xiang)膠(jiao)早期是由美(mei)國(guo)以三氯化(hua)鐵為催(cui)化(hua)劑合成的(de)。1945年(nian),硅(gui)(gui)橡(xiang)(xiang)膠(jiao)產(chan)品問(wen)世。1948年(nian),采(cai)用(yong)高比表面積的(de)氣相(xiang)法(fa)白(bai)炭(tan)黑補強的(de)硅(gui)(gui)橡(xiang)(xiang)膠(jiao)研(yan)制成功(gong),使(shi)硅(gui)(gui)橡(xiang)(xiang)膠(jiao)的(de)性能(neng)躍升到實(shi)用(yong)階段,奠定了現(xian)代硅(gui)(gui)橡(xiang)(xiang)膠(jiao)生(sheng)產(chan)技術的(de)基礎(chu)。從二(er)甲基二(er)氯硅(gui)(gui)烷合成開(kai)始(shi)生(sheng)產(chan)硅(gui)(gui)橡(xiang)(xiang)膠(jiao)的(de)國(guo)家有美(mei)國(guo)。俄羅斯、德國(guo)、日本、韓(han)國(guo)和中(zhong)(zhong)(zhong)國(guo)等(deng)。中(zhong)(zhong)(zhong)國(guo)硅(gui)(gui)橡(xiang)(xiang)膠(jiao)的(de)工(gong)業(ye)(ye)化(hua)研(yan)究始(shi)于(yu)1957年(nian),多家研(yan)究所和企業(ye)(ye)陸(lu)續開(kai)發出(chu)各種硅(gui)(gui)橡(xiang)(xiang)膠(jiao)。到2003年(nian)底,中(zhong)(zhong)(zhong)國(guo)硅(gui)(gui)橡(xiang)(xiang)膠(jiao)生(sheng)產(chan)能(neng)力為135千噸(dun),其中(zhong)(zhong)(zhong)高溫膠(jiao)100千噸(dun)。
高溫硫(liu)化硅橡膠
高(gao)溫硫(liu)(liu)(liu)化(hua)(hua)硅(gui)橡膠(jiao)(jiao)是(shi)(shi)指聚(ju)硅(gui)氧烷(wan)變成(cheng)(cheng)彈性體的(de)過(guo)程是(shi)(shi)經過(guo)高(gao)溫(110-170℃)硫(liu)(liu)(liu)化(hua)(hua)成(cheng)(cheng)型的(de)。它主要(yao)(yao)以(yi)高(gao)分子量的(de)聚(ju)甲基(ji)(ji)乙(yi)烯基(ji)(ji)硅(gui)氧烷(wan)為生(sheng)膠(jiao)(jiao),混入(ru)補強填料、硫(liu)(liu)(liu)化(hua)(hua)劑等,在(zai)加(jia)熱加(jia)壓下硫(liu)(liu)(liu)化(hua)(hua)成(cheng)(cheng)彈性體。硅(gui)橡膠(jiao)(jiao)的(de)補強主要(yao)(yao)是(shi)(shi)各種(zhong)類型的(de)白炭(tan)黑,可使硫(liu)(liu)(liu)化(hua)(hua)膠(jiao)(jiao)的(de)強度增加(jia)數十倍。有時(shi)為了降(jiang)低(di)成(cheng)(cheng)本或(huo)改善膠(jiao)(jiao)料性能及賦予硫(liu)(liu)(liu)化(hua)(hua)膠(jiao)(jiao)各種(zhong)特殊的(de)性能,也加(jia)入(ru)相應的(de)各種(zhong)添(tian)加(jia)劑。硫(liu)(liu)(liu)化(hua)(hua)劑是(shi)(shi)各種(zhong)有機過(guo)氧化(hua)(hua)物或(huo)加(jia)成(cheng)(cheng)反應催化(hua)(hua)劑。
加工成型方法(fa)如圖所示。一(yi)次(ci)硫(liu)化(hua)的目(mu)的是(shi)進行(xing)高分子鏈的交(jiao)聯反應(ying);二(er)次(ci)硫(liu)化(hua)的目(mu)的是(shi)進行(xing)補充(chong)交(jiao)聯、驅除硫(liu)化(hua)劑分解產物和其(qi)他揮發(fa)性化(hua)合(he)物以穩定硫(liu)化(hua)膠的各項性能。常用的設備有開放式煉膠機、捏合(he)機及真空密煉機。
主要性能
(1)高溫(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)。硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)顯(xian)著的(de)(de)(de)(de)特(te)征是高溫(wen)(wen)穩定性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing),雖然(ran)常溫(wen)(wen)下(xia)(xia)硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)的(de)(de)(de)(de)強度(du)(du)僅是天(tian)然(ran)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)或某些合成橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)的(de)(de)(de)(de)一半,但(dan)在(zai)200℃以(yi)上的(de)(de)(de)(de)高溫(wen)(wen)環境下(xia)(xia),硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)仍能(neng)(neng)保持一定的(de)(de)(de)(de)柔韌(ren)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)、回(hui)彈性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)和(he)表面硬度(du)(du),且力學性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)無明(ming)顯(xian)變化。(2)低溫(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)的(de)(de)(de)(de)玻璃化溫(wen)(wen)度(du)(du)一般為-70~-50℃,特(te)殊配方可達-100℃,表明(ming)其低溫(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)優(you)異。這(zhe)對航空(kong)、宇航工業的(de)(de)(de)(de)意義重大(da)。(3)耐(nai)(nai)(nai)候性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)中Si-O-Si鍵對氧、臭(chou)氧及紫外線等十分穩定,在(zai)不加(jia)任何添加(jia)劑的(de)(de)(de)(de)情況下(xia)(xia),就具(ju)有優(you)良的(de)(de)(de)(de)耐(nai)(nai)(nai)候性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)。(4)電(dian)氣性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)。硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)具(ju)有優(you)異的(de)(de)(de)(de)絕緣性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng),耐(nai)(nai)(nai)電(dian)暈(yun)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)和(he)耐(nai)(nai)(nai)電(dian)弧性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)也非常好。(5)物理機(ji)(ji)械(xie)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)。硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)常溫(wen)(wen)下(xia)(xia)的(de)(de)(de)(de)物理機(ji)(ji)械(xie)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)比通用橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)差,但(dan)在(zai)150℃的(de)(de)(de)(de)高溫(wen)(wen)和(he)-50℃的(de)(de)(de)(de)低溫(wen)(wen)下(xia)(xia),其物理機(ji)(ji)械(xie)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)優(you)于(yu)通用橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)。(6)耐(nai)(nai)(nai)油(you)及化學試劑性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)。普(pu)通硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)具(ju)有中等的(de)(de)(de)(de)耐(nai)(nai)(nai)油(you)、耐(nai)(nai)(nai)溶劑性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)。(7)氣體透(tou)過性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)。室溫(wen)(wen)下(xia)(xia)硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)對空(kong)氣、氮、氧、二氧化碳等氣體的(de)(de)(de)(de)透(tou)氣性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)比天(tian)然(ran)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)高出30-50倍。(8)生理惰(duo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)。硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)(jiao)無毒,無味(wei),無嗅,與(yu)人體組織(zhi)(zhi)不粘連,具(ju)有抗凝(ning)血作用,對肌體組織(zhi)(zhi)的(de)(de)(de)(de)反應性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)非常少。特(te)別適(shi)合作為醫用材料。
硅橡(xiang)膠的用(yong)量
據中國(guo)(guo)汽(qi)(qi)(qi)(qi)(qi)(qi)車(che)(che)(che)(che)工(gong)業(ye)(ye)協會(hui)統計,2012年,汽(qi)(qi)(qi)(qi)(qi)(qi)車(che)(che)(che)(che)產(chan)(chan)銷分別(bie)達(da)到1927.18萬(wan)輛(liang)和(he)1930.64萬(wan)輛(liang),同(tong)比分別(bie)增(zeng)(zeng)長4.63%和(he)4.33%,汽(qi)(qi)(qi)(qi)(qi)(qi)車(che)(che)(che)(che)工(gong)業(ye)(ye)硅(gui)橡膠(jiao)的用(yong)(yong)量(liang)約達(da)2.0萬(wan)t。根(gen)據觀研天下的新(xin)研究,增(zeng)(zeng)加(jia)有機硅(gui)材料在汽(qi)(qi)(qi)(qi)(qi)(qi)車(che)(che)(che)(che)零(ling)部件(jian)方面的用(yong)(yong)量(liang),可(ke)以大幅度提(ti)高(gao)汽(qi)(qi)(qi)(qi)(qi)(qi)車(che)(che)(che)(che)的安全性(xing)能,因此,汽(qi)(qi)(qi)(qi)(qi)(qi)車(che)(che)(che)(che)產(chan)(chan)量(liang)和(he)單車(che)(che)(che)(che)用(yong)(yong)量(liang)水平的提(ti)高(gao)都將(jiang)(jiang)推動汽(qi)(qi)(qi)(qi)(qi)(qi)車(che)(che)(che)(che)工(gong)業(ye)(ye)對硅(gui)橡膠(jiao)需求的增(zeng)(zeng)加(jia)。國(guo)(guo)家鼓勵自(zi)(zi)主(zhu)(zhu)品(pin)牌(pai)(pai)(pai)的汽(qi)(qi)(qi)(qi)(qi)(qi)車(che)(che)(che)(che)發展,關(guan)鍵汽(qi)(qi)(qi)(qi)(qi)(qi)車(che)(che)(che)(che)零(ling)部件(jian)實現(xian)自(zi)(zi)主(zhu)(zhu)化,《2012年度黨政(zheng)(zheng)機關(guan)公務用(yong)(yong)車(che)(che)(che)(che)選用(yong)(yong)車(che)(che)(che)(che)型目錄(征(zheng)求意見稿(gao))》為自(zi)(zi)主(zhu)(zhu)品(pin)牌(pai)(pai)(pai)擴大在政(zheng)(zheng)府(fu)采購(gou)的市場份額(e),為改變(bian)目前國(guo)(guo)內政(zheng)(zheng)府(fu)采購(gou)以合(he)資品(pin)牌(pai)(pai)(pai)產(chan)(chan)品(pin)為主(zhu)(zhu)的局(ju)面提(ti)供(gong)了保(bao)(bao)障。促進自(zi)(zi)主(zhu)(zhu)品(pin)牌(pai)(pai)(pai)發展,國(guo)(guo)產(chan)(chan)汽(qi)(qi)(qi)(qi)(qi)(qi)車(che)(che)(che)(che)業(ye)(ye)的繁榮將(jiang)(jiang)為汽(qi)(qi)(qi)(qi)(qi)(qi)車(che)(che)(che)(che)膠(jiao)的應(ying)用(yong)(yong)提(ti)供(gong)有力(li)保(bao)(bao)障。預測未來3年,我國(guo)(guo)室溫硫化硅(gui)橡膠(jiao)在汽(qi)(qi)(qi)(qi)(qi)(qi)車(che)(che)(che)(che)行業(ye)(ye)將(jiang)(jiang)以年均(jun)20%增(zeng)(zeng)長。
此外,硅(gui)(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)是重要(yao)的(de)(de)非石油(you)(you)(you)基(ji)(ji)(ji)合(he)成(cheng)(cheng)橡(xiang)膠(jiao)(jiao),約占非石油(you)(you)(you)基(ji)(ji)(ji)合(he)成(cheng)(cheng)橡(xiang)膠(jiao)(jiao)消費量的(de)(de)98%。但因為(wei)(wei)石油(you)(you)(you)價格的(de)(de)大(da)幅(fu)上漲(zhang),同(tong)時我國(guo)(guo)在硅(gui)(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)的(de)(de)關(guan)鍵原料有(you)機(ji)硅(gui)(gui)(gui)(gui)單(dan)體的(de)(de)生產(chan)技術方面取得突破,有(you)機(ji)硅(gui)(gui)(gui)(gui)單(dan)體的(de)(de)生產(chan)技術在2005年(nian)前被幾家跨國(guo)(guo)公司(si)壟(long)斷,但目前我國(guo)(guo)已發展(zhan)成(cheng)(cheng)為(wei)(wei)全(quan)球有(you)機(ji)硅(gui)(gui)(gui)(gui)單(dan)體第1大(da)國(guo)(guo),這(zhe)2個(ge)方面原因使(shi)硅(gui)(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)的(de)(de)價格從2011年(nian)起(qi)開始低(di)于石油(you)(you)(you)基(ji)(ji)(ji)合(he)成(cheng)(cheng)橡(xiang)膠(jiao)(jiao),僅約為(wei)(wei)大(da)宗石油(you)(you)(you)基(ji)(ji)(ji)橡(xiang)膠(jiao)(jiao)的(de)(de)80%~90%,成(cheng)(cheng)為(wei)(wei)廉價的(de)(de)合(he)成(cheng)(cheng)橡(xiang)膠(jiao)(jiao),并開始大(da)規(gui)模替(ti)代石油(you)(you)(you)基(ji)(ji)(ji)合(he)成(cheng)(cheng)橡(xiang)膠(jiao)(jiao)。這(zhe)將極大(da)拓展(zhan)有(you)機(ji)硅(gui)(gui)(gui)(gui)產(chan)業(ye)的(de)(de)市場空(kong)間,同(tong)時將帶動硅(gui)(gui)(gui)(gui)油(you)(you)(you)、硅(gui)(gui)(gui)(gui)烷(wan)偶聯劑和硅(gui)(gui)(gui)(gui)樹脂等其(qi)他有(you)機(ji)硅(gui)(gui)(gui)(gui)產(chan)品的(de)(de)消費。