橡(xiang)(xiang)膠(jiao)(jiao)(jiao),同塑料、纖維并稱為(wei)三大合成材料,是(shi)只有一個具(ju)有高(gao)(gao)(gao)(gao)度伸縮(suo)性(xing)(xing)與極(ji)好彈性(xing)(xing)的(de)高(gao)(gao)(gao)(gao)分子材料。橡(xiang)(xiang)膠(jiao)(jiao)(jiao)的(de)較大特(te)征(zheng)首先是(shi)彈性(xing)(xing)模量非(fei)常(chang)小,而(er)伸長率(lv)很高(gao)(gao)(gao)(gao)。其次是(shi)它(ta)具(ju)有相當(dang)好的(de)耐(nai)透氣性(xing)(xing)以(yi)(yi)及(ji)耐(nai)各種(zhong)(zhong)化學介質和電絕(jue)緣的(de)性(xing)(xing)能(neng)(neng)(neng)。某些(xie)特(te)種(zhong)(zhong)合成橡(xiang)(xiang)膠(jiao)(jiao)(jiao)更具(ju)備良好的(de)耐(nai)油(you)(you)(you)性(xing)(xing)及(ji)耐(nai)溫(wen)性(xing)(xing),能(neng)(neng)(neng)抵(di)抗(kang)脂肪油(you)(you)(you)、潤(run)滑油(you)(you)(you)、液(ye)壓油(you)(you)(you)、燃料油(you)(you)(you)以(yi)(yi)及(ji)溶劑油(you)(you)(you)的(de)溶脹;耐(nai)寒可(ke)(ke)低到(dao)-60℃至-80℃,耐(nai)熱可(ke)(ke)高(gao)(gao)(gao)(gao)到(dao)+180℃至+350℃。橡(xiang)(xiang)膠(jiao)(jiao)(jiao)還(huan)耐(nai)各種(zhong)(zhong)曲撓、彎曲變(bian)形,因為(wei)滯后損失小。橡(xiang)(xiang)膠(jiao)(jiao)(jiao)的(de)第三個特(te)征(zheng)在于它(ta)能(neng)(neng)(neng)與多種(zhong)(zhong)材料進行(xing)并用、共混、復合,由此進行(xing)改性(xing)(xing),以(yi)(yi)得到(dao)良好的(de)綜合性(xing)(xing)能(neng)(neng)(neng)。橡(xiang)(xiang)膠(jiao)(jiao)(jiao)的(de)這些(xie)基本(ben)性(xing)(xing)能(neng)(neng)(neng),是(shi)它(ta)成為(wei)工業上極(ji)好的(de)減震、密封、屈撓、耐(nai)磨、防腐、絕(jue)緣以(yi)(yi)及(ji)粘接等材料。
工業用橡(xiang)膠品(pin)種很多,按材料來源可分為天然橡(xiang)膠(Natural Rubber)和(he)合成(cheng)橡(xiang)膠(Synthetic Rubber)兩(liang)大類。按其性(xing)能和(he)用途可分為通用橡(xiang)膠(Universal Rubber)和(he)特種橡(xiang)膠(Specialty Rubber Eastomer)兩(liang)大類。
凡是性(xing)能(neng)與天然橡(xiang)膠(jiao)(jiao)相同或接近,物理性(xing)能(neng)和加工(gong)性(xing)能(neng)較好,能(neng)廣泛用(yong)于輪胎和其它一般橡(xiang)膠(jiao)(jiao)制(zhi)品的橡(xiang)膠(jiao)(jiao)稱為通用(yong)橡(xiang)膠(jiao)(jiao)。通用(yong)橡(xiang)膠(jiao)(jiao)有:天然橡(xiang)膠(jiao)(jiao)(NR)、丁(ding)苯橡(xiang)膠(jiao)(jiao)(SBR)、順丁(ding)橡(xiang)膠(jiao)(jiao)(聚丁(ding)二烯橡(xiang)膠(jiao)(jiao),BR)、異戊橡(xiang)膠(jiao)(jiao)(聚異戊二烯橡(xiang)膠(jiao)(jiao),IR)
凡是具(ju)有特(te)(te)殊性能,專供耐(nai)熱、耐(nai)寒、耐(nai)化(hua)學(xue)腐蝕、耐(nai)油、耐(nai)溶劑、耐(nai)輻射等(deng)特(te)(te)殊性能橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)制品使(shi)用的稱為特(te)(te)種橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)。特(te)(te)種橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)有:丁(ding)(ding)腈橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(NBR)、硅橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)、氟橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)、聚氨(an)酯橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)、聚硫橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)、聚丙烯(xi)酸酯橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(UR)、氯醚橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)、氯化(hua)聚乙烯(xi)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)(CPE)、氯磺(huang)化(hua)聚乙烯(xi)(CSM)、丁(ding)(ding)吡(bi)橡(xiang)(xiang)(xiang)膠(jiao)(jiao)(jiao)等(deng)。
實際上(shang),通用橡(xiang)膠(jiao)(jiao)和特種橡(xiang)膠(jiao)(jiao)之(zhi)間并無(wu)嚴格的(de)界(jie)限(xian),如乙丙(bing)(bing)橡(xiang)膠(jiao)(jiao)兼具上(shang)述(shu)兩方面(mian)的(de)特點。通用橡(xiang)膠(jiao)(jiao)與特種橡(xiang)膠(jiao)(jiao)之(zhi)間的(de)有(you):氯(lv)丁(ding)橡(xiang)膠(jiao)(jiao)(CR)、乙丙(bing)(bing)橡(xiang)膠(jiao)(jiao)(EPDM)、丁(ding)基橡(xiang)膠(jiao)(jiao)(IIR)