硅橡膠是(shi)指主(zhu)鏈(lian)由(you)硅(gui)(gui)和(he)(he)氧原子交替構成,硅(gui)(gui)原子上通(tong)常連有(you)兩個有(you)機(ji)基(ji)團的(de)(de)(de)橡(xiang)(xiang)(xiang)膠(jiao)。普通(tong)的(de)(de)(de)硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)主(zhu)要由(you)含甲基(ji)和(he)(he)少量乙烯基(ji)的(de)(de)(de)硅(gui)(gui)氧鏈(lian)節組成。苯基(ji)的(de)(de)(de)引(yin)入(ru)可(ke)提高(gao)(gao)硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)的(de)(de)(de)耐(nai)高(gao)(gao)、低溫性(xing)(xing)能(neng)(neng)(neng),三氟丙基(ji)及氰(qing)基(ji)的(de)(de)(de)引(yin)入(ru)則(ze)可(ke)提高(gao)(gao)硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)的(de)(de)(de)耐(nai)溫及耐(nai)油性(xing)(xing)能(neng)(neng)(neng)。硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)耐(nai)低溫性(xing)(xing)能(neng)(neng)(neng)良好,一般在(zai)(zai)-55℃下仍(reng)(reng)能(neng)(neng)(neng)工(gong)作(zuo)。引(yin)入(ru)苯基(ji)后,可(ke)達-73℃。硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)的(de)(de)(de)耐(nai)熱性(xing)(xing)能(neng)(neng)(neng)也(ye)(ye)很突出,在(zai)(zai)180℃下可(ke)長期工(gong)作(zuo),稍(shao)高(gao)(gao)于200℃也(ye)(ye)能(neng)(neng)(neng)承受數周或更長時(shi)間(jian)仍(reng)(reng)有(you)彈(dan)性(xing)(xing),瞬時(shi)可(ke)耐(nai)300℃以上的(de)(de)(de)高(gao)(gao)溫。硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)的(de)(de)(de)透氣(qi)性(xing)(xing)好,氧氣(qi)透過率在(zai)(zai)合成聚(ju)合物中是(shi)較高(gao)(gao)的(de)(de)(de)。此外(wai),硅(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)還(huan)具有(you)生(sheng)理惰(duo)性(xing)(xing)、不(bu)會(hui)導致凝血(xue)的(de)(de)(de)突出特性(xing)(xing),因此在(zai)(zai)醫用領域應用廣(guang)泛(fan)。
主要品種
硅(gui)(gui)(gui)橡(xiang)膠(jiao)分(fen)(fen)類的(de)方(fang)法很多(duo),通常(chang)按(an)(an)固(gu)(gu)化前的(de)形態分(fen)(fen)為(wei)固(gu)(gu)體(ti)硅(gui)(gui)(gui)橡(xiang)膠(jiao)和液體(ti)硅(gui)(gui)(gui)橡(xiang)膠(jiao);按(an)(an)硫(liu)化溫度分(fen)(fen)為(wei)室溫硫(liu)化硅(gui)(gui)(gui)橡(xiang)膠(jiao),高溫硫(liu)化硅(gui)(gui)(gui)橡(xiang)膠(jiao);按(an)(an)所用單體(ti)的(de)不同,可(ke)分(fen)(fen)為(wei)甲基(ji)(ji)乙烯(xi)基(ji)(ji)硅(gui)(gui)(gui)橡(xiang)膠(jiao),甲基(ji)(ji)苯(ben)基(ji)(ji)乙烯(xi)基(ji)(ji)硅(gui)(gui)(gui)橡(xiang)膠(jiao)、氟硅(gui)(gui)(gui),腈硅(gui)(gui)(gui)橡(xiang)膠(jiao)等(deng);按(an)(an)性能和用途的(de)不同又可(ke)分(fen)(fen)為(wei)通用型(xing)(xing)(xing)(xing)、超(chao)耐低溫型(xing)(xing)(xing)(xing)、超(chao)耐高溫型(xing)(xing)(xing)(xing)、高強力型(xing)(xing)(xing)(xing)、耐油型(xing)(xing)(xing)(xing)、醫用型(xing)(xing)(xing)(xing)等(deng)等(deng)。
發展史
硅(gui)橡(xiang)膠(jiao)(jiao)早期是由美(mei)國(guo)以(yi)三氯化鐵為催化劑(ji)合成的。1945年,硅(gui)橡(xiang)膠(jiao)(jiao)產品問世(shi)。1948年,采用高(gao)比(bi)表面積的氣相法白(bai)炭黑(hei)補強的硅(gui)橡(xiang)膠(jiao)(jiao)研(yan)制成功,使硅(gui)橡(xiang)膠(jiao)(jiao)的性(xing)能(neng)躍(yue)升(sheng)到(dao)實用階段,奠定(ding)了現代硅(gui)橡(xiang)膠(jiao)(jiao)生(sheng)(sheng)產技術(shu)的基(ji)礎。從(cong)二(er)甲基(ji)二(er)氯硅(gui)烷合成開(kai)始生(sheng)(sheng)產硅(gui)橡(xiang)膠(jiao)(jiao)的國(guo)家有美(mei)國(guo)。俄(e)羅(luo)斯、德國(guo)、日本、韓國(guo)和中(zhong)國(guo)等(deng)。中(zhong)國(guo)硅(gui)橡(xiang)膠(jiao)(jiao)的工業(ye)化研(yan)究始于1957年,多家研(yan)究所和企(qi)業(ye)陸(lu)續開(kai)發出各種硅(gui)橡(xiang)膠(jiao)(jiao)。到(dao)2003年底(di),中(zhong)國(guo)硅(gui)橡(xiang)膠(jiao)(jiao)生(sheng)(sheng)產能(neng)力為135千噸,其中(zhong)高(gao)溫膠(jiao)(jiao)100千噸。
高溫硫化硅橡膠
高溫硫(liu)化(hua)(hua)硅橡膠(jiao)是(shi)(shi)(shi)(shi)指聚硅氧烷變成(cheng)彈(dan)性(xing)體(ti)的(de)過程是(shi)(shi)(shi)(shi)經(jing)過高溫(110-170℃)硫(liu)化(hua)(hua)成(cheng)型(xing)的(de)。它主要(yao)以高分(fen)子量(liang)的(de)聚甲基乙烯(xi)基硅氧烷為(wei)生膠(jiao),混入補(bu)強填料、硫(liu)化(hua)(hua)劑(ji)(ji)等,在加(jia)(jia)熱加(jia)(jia)壓(ya)下硫(liu)化(hua)(hua)成(cheng)彈(dan)性(xing)體(ti)。硅橡膠(jiao)的(de)補(bu)強主要(yao)是(shi)(shi)(shi)(shi)各種類型(xing)的(de)白炭黑,可使(shi)硫(liu)化(hua)(hua)膠(jiao)的(de)強度增加(jia)(jia)數十(shi)倍。有(you)時(shi)為(wei)了降低成(cheng)本或改善膠(jiao)料性(xing)能及賦予(yu)硫(liu)化(hua)(hua)膠(jiao)各種特殊(shu)的(de)性(xing)能,也(ye)加(jia)(jia)入相應(ying)的(de)各種添加(jia)(jia)劑(ji)(ji)。硫(liu)化(hua)(hua)劑(ji)(ji)是(shi)(shi)(shi)(shi)各種有(you)機過氧化(hua)(hua)物(wu)或加(jia)(jia)成(cheng)反(fan)應(ying)催化(hua)(hua)劑(ji)(ji)。
加工成型方法如圖所示。一(yi)次硫(liu)化的(de)目(mu)的(de)是(shi)進行高分子鏈的(de)交(jiao)聯反應;二次硫(liu)化的(de)目(mu)的(de)是(shi)進行補充交(jiao)聯、驅除(chu)硫(liu)化劑分解(jie)產(chan)物和其他揮發性(xing)化合物以穩定硫(liu)化膠的(de)各項(xiang)性(xing)能。常用的(de)設備有開放式煉膠機(ji)、捏合機(ji)及真空(kong)密煉機(ji)。
主要性能
(1)高(gao)溫(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)。硅(gui)橡膠(jiao)(jiao)(jiao)(jiao)顯(xian)著的(de)(de)(de)特(te)征是高(gao)溫(wen)(wen)穩(wen)定(ding)性(xing)(xing)(xing)(xing)(xing)(xing),雖(sui)然常溫(wen)(wen)下(xia)硅(gui)橡膠(jiao)(jiao)(jiao)(jiao)的(de)(de)(de)強度(du)(du)僅是天然橡膠(jiao)(jiao)(jiao)(jiao)或某些合(he)成橡膠(jiao)(jiao)(jiao)(jiao)的(de)(de)(de)一半,但在200℃以(yi)上(shang)的(de)(de)(de)高(gao)溫(wen)(wen)環境下(xia),硅(gui)橡膠(jiao)(jiao)(jiao)(jiao)仍能(neng)(neng)(neng)(neng)保持一定(ding)的(de)(de)(de)柔韌性(xing)(xing)(xing)(xing)(xing)(xing)、回(hui)彈性(xing)(xing)(xing)(xing)(xing)(xing)和表面硬度(du)(du),且(qie)力學性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)無(wu)明顯(xian)變化(hua)。(2)低溫(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)硅(gui)橡膠(jiao)(jiao)(jiao)(jiao)的(de)(de)(de)玻璃(li)化(hua)溫(wen)(wen)度(du)(du)一般為(wei)(wei)-70~-50℃,特(te)殊配方可達-100℃,表明其低溫(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)優異(yi)。這(zhe)對(dui)航(hang)空(kong)、宇航(hang)工業(ye)的(de)(de)(de)意義重大。(3)耐(nai)(nai)候性(xing)(xing)(xing)(xing)(xing)(xing)硅(gui)橡膠(jiao)(jiao)(jiao)(jiao)中Si-O-Si鍵對(dui)氧(yang)、臭氧(yang)及(ji)紫外線等十分穩(wen)定(ding),在不(bu)加任何添加劑的(de)(de)(de)情況(kuang)下(xia),就具(ju)有(you)優良的(de)(de)(de)耐(nai)(nai)候性(xing)(xing)(xing)(xing)(xing)(xing)。(4)電氣性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)。硅(gui)橡膠(jiao)(jiao)(jiao)(jiao)具(ju)有(you)優異(yi)的(de)(de)(de)絕緣性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng),耐(nai)(nai)電暈性(xing)(xing)(xing)(xing)(xing)(xing)和耐(nai)(nai)電弧性(xing)(xing)(xing)(xing)(xing)(xing)也非常好。(5)物(wu)理(li)(li)機(ji)械性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)。硅(gui)橡膠(jiao)(jiao)(jiao)(jiao)常溫(wen)(wen)下(xia)的(de)(de)(de)物(wu)理(li)(li)機(ji)械性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)比(bi)通(tong)用(yong)(yong)橡膠(jiao)(jiao)(jiao)(jiao)差,但在150℃的(de)(de)(de)高(gao)溫(wen)(wen)和-50℃的(de)(de)(de)低溫(wen)(wen)下(xia),其物(wu)理(li)(li)機(ji)械性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)優于通(tong)用(yong)(yong)橡膠(jiao)(jiao)(jiao)(jiao)。(6)耐(nai)(nai)油(you)(you)及(ji)化(hua)學試劑性(xing)(xing)(xing)(xing)(xing)(xing)。普(pu)通(tong)硅(gui)橡膠(jiao)(jiao)(jiao)(jiao)具(ju)有(you)中等的(de)(de)(de)耐(nai)(nai)油(you)(you)、耐(nai)(nai)溶劑性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)。(7)氣體(ti)透(tou)過性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)。室(shi)溫(wen)(wen)下(xia)硅(gui)橡膠(jiao)(jiao)(jiao)(jiao)對(dui)空(kong)氣、氮、氧(yang)、二氧(yang)化(hua)碳等氣體(ti)的(de)(de)(de)透(tou)氣性(xing)(xing)(xing)(xing)(xing)(xing)比(bi)天然橡膠(jiao)(jiao)(jiao)(jiao)高(gao)出(chu)30-50倍。(8)生(sheng)理(li)(li)惰性(xing)(xing)(xing)(xing)(xing)(xing)。硅(gui)橡膠(jiao)(jiao)(jiao)(jiao)無(wu)毒(du),無(wu)味,無(wu)嗅(xiu),與(yu)人體(ti)組(zu)織(zhi)不(bu)粘連(lian),具(ju)有(you)抗凝(ning)血作用(yong)(yong),對(dui)肌體(ti)組(zu)織(zhi)的(de)(de)(de)反應(ying)性(xing)(xing)(xing)(xing)(xing)(xing)非常少。特(te)別(bie)適(shi)合(he)作為(wei)(wei)醫用(yong)(yong)材料(liao)。
硅橡膠的用量
據(ju)(ju)中(zhong)國(guo)汽(qi)(qi)(qi)(qi)(qi)車(che)(che)(che)工(gong)(gong)業(ye)協會統計,2012年(nian),汽(qi)(qi)(qi)(qi)(qi)車(che)(che)(che)產(chan)銷(xiao)分別達到1927.18萬輛和1930.64萬輛,同比(bi)分別增長(chang)4.63%和4.33%,汽(qi)(qi)(qi)(qi)(qi)車(che)(che)(che)工(gong)(gong)業(ye)硅橡(xiang)膠(jiao)的(de)(de)(de)用(yong)(yong)(yong)量(liang)約達2.0萬t。根據(ju)(ju)觀研天下的(de)(de)(de)新研究,增加有機(ji)硅材料(liao)在(zai)(zai)汽(qi)(qi)(qi)(qi)(qi)車(che)(che)(che)零部件方(fang)面的(de)(de)(de)用(yong)(yong)(yong)量(liang),可(ke)以大幅度提(ti)高(gao)汽(qi)(qi)(qi)(qi)(qi)車(che)(che)(che)的(de)(de)(de)安全性能,因此(ci),汽(qi)(qi)(qi)(qi)(qi)車(che)(che)(che)產(chan)量(liang)和單車(che)(che)(che)用(yong)(yong)(yong)量(liang)水(shui)平(ping)的(de)(de)(de)提(ti)高(gao)都(dou)將(jiang)推動汽(qi)(qi)(qi)(qi)(qi)車(che)(che)(che)工(gong)(gong)業(ye)對硅橡(xiang)膠(jiao)需求的(de)(de)(de)增加。國(guo)家(jia)鼓勵(li)自(zi)(zi)主(zhu)品(pin)牌的(de)(de)(de)汽(qi)(qi)(qi)(qi)(qi)車(che)(che)(che)發展,關鍵汽(qi)(qi)(qi)(qi)(qi)車(che)(che)(che)零部件實現(xian)自(zi)(zi)主(zhu)化(hua),《2012年(nian)度黨政(zheng)機(ji)關公務(wu)用(yong)(yong)(yong)車(che)(che)(che)選用(yong)(yong)(yong)車(che)(che)(che)型目錄(征(zheng)求意見稿(gao))》為(wei)自(zi)(zi)主(zhu)品(pin)牌擴大在(zai)(zai)政(zheng)府(fu)采購的(de)(de)(de)市場(chang)份額(e),為(wei)改變(bian)目前國(guo)內(nei)政(zheng)府(fu)采購以合(he)資品(pin)牌產(chan)品(pin)為(wei)主(zhu)的(de)(de)(de)局面提(ti)供(gong)了(le)保(bao)障。促進自(zi)(zi)主(zhu)品(pin)牌發展,國(guo)產(chan)汽(qi)(qi)(qi)(qi)(qi)車(che)(che)(che)業(ye)的(de)(de)(de)繁榮將(jiang)為(wei)汽(qi)(qi)(qi)(qi)(qi)車(che)(che)(che)膠(jiao)的(de)(de)(de)應用(yong)(yong)(yong)提(ti)供(gong)有力保(bao)障。預測(ce)未來(lai)3年(nian),我(wo)國(guo)室溫硫(liu)化(hua)硅橡(xiang)膠(jiao)在(zai)(zai)汽(qi)(qi)(qi)(qi)(qi)車(che)(che)(che)行業(ye)將(jiang)以年(nian)均20%增長(chang)。
此外(wai),硅(gui)(gui)(gui)(gui)橡(xiang)膠是(shi)重要的(de)非(fei)石(shi)油(you)(you)(you)基(ji)合(he)(he)成(cheng)(cheng)(cheng)(cheng)橡(xiang)膠,約占(zhan)非(fei)石(shi)油(you)(you)(you)基(ji)合(he)(he)成(cheng)(cheng)(cheng)(cheng)橡(xiang)膠消(xiao)費量(liang)的(de)98%。但因(yin)為(wei)石(shi)油(you)(you)(you)價(jia)格(ge)的(de)大(da)幅(fu)上(shang)漲(zhang),同時(shi)我國(guo)在硅(gui)(gui)(gui)(gui)橡(xiang)膠的(de)關鍵原料有(you)(you)機(ji)(ji)硅(gui)(gui)(gui)(gui)單體(ti)的(de)生(sheng)產(chan)技術方面取得突(tu)破,有(you)(you)機(ji)(ji)硅(gui)(gui)(gui)(gui)單體(ti)的(de)生(sheng)產(chan)技術在2005年前(qian)被幾家跨國(guo)公司壟斷,但目(mu)前(qian)我國(guo)已發展成(cheng)(cheng)(cheng)(cheng)為(wei)全球有(you)(you)機(ji)(ji)硅(gui)(gui)(gui)(gui)單體(ti)第1大(da)國(guo),這(zhe)2個方面原因(yin)使硅(gui)(gui)(gui)(gui)橡(xiang)膠的(de)價(jia)格(ge)從(cong)2011年起開始低于石(shi)油(you)(you)(you)基(ji)合(he)(he)成(cheng)(cheng)(cheng)(cheng)橡(xiang)膠,僅約為(wei)大(da)宗石(shi)油(you)(you)(you)基(ji)橡(xiang)膠的(de)80%~90%,成(cheng)(cheng)(cheng)(cheng)為(wei)廉價(jia)的(de)合(he)(he)成(cheng)(cheng)(cheng)(cheng)橡(xiang)膠,并開始大(da)規模替代石(shi)油(you)(you)(you)基(ji)合(he)(he)成(cheng)(cheng)(cheng)(cheng)橡(xiang)膠。這(zhe)將極大(da)拓(tuo)展有(you)(you)機(ji)(ji)硅(gui)(gui)(gui)(gui)產(chan)業的(de)市場空間,同時(shi)將帶動硅(gui)(gui)(gui)(gui)油(you)(you)(you)、硅(gui)(gui)(gui)(gui)烷偶(ou)聯劑和硅(gui)(gui)(gui)(gui)樹脂等其(qi)他有(you)(you)機(ji)(ji)硅(gui)(gui)(gui)(gui)產(chan)品的(de)消(xiao)費。