橡胶是指(zhi)具有可(ke)逆形变的高弹性(xing)聚合(he)物材料(liao)，在室温(wen)下富(fu)有弹性(xing)，在很(hen)小的外(wai)力作用(yong)下能产生较(jiao)大(da)形变，除(chu)去外(wai)力后能恢(hui)复(fu)原状。橡胶属于(yu)完全(quan)无定型聚合(he)物，它的玻璃(li)化转(zhuan)变温(wen)度（T g）低，分子量往往很(hen)大(da)，大(da)于(yu)几十万。

橡(xiang)(xiang)胶(jiao)分为天然橡(xiang)(xiang)胶(jiao)与合成(cheng)橡(xiang)(xiang)胶(jiao)二(er)种(zhong)。天然橡(xiang)(xiang)胶(jiao)是从(cong)橡(xiang)(xiang)胶(jiao)树、橡(xiang)(xiang)胶(jiao)草等(deng)植物中(zhong)提取胶(jiao)质后(hou)加工制(zhi)成(cheng)；合成(cheng)橡(xiang)(xiang)胶(jiao)则由(you)各(ge)种(zhong)单(dan)体经聚合反应而(er)得。橡(xiang)(xiang)胶(jiao)制(zhi)品广泛(fan)应用于(yu)工业或生活各(ge)方面。

通用(yong)(yong)(yong)型(xing)橡(xiang)(xiang)(xiang)(xiang)(xiang)胶(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)的(de)(de)(de)综(zong)(zong)(zong)合(he)(he)性(xing)(xing)(xing)能(neng)较好(hao)(hao)，应(ying)用(yong)(yong)(yong)广(guang)泛。主(zhu)要(yao)有：①天(tian)然(ran)(ran)橡(xiang)(xiang)(xiang)(xiang)(xiang)胶(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)，从三叶橡(xiang)(xiang)(xiang)(xiang)(xiang)胶(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)树的(de)(de)(de)乳(ru)胶(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)制(zhi)得(de)，基本化(hua)学成分为顺- 聚(ju)异(yi)戊(wu)二烯(xi)。弹性(xing)(xing)(xing)好(hao)(hao)，强度(du)高，综(zong)(zong)(zong)合(he)(he)性(xing)(xing)(xing)能(neng)好(hao)(hao)。②异(yi)戊(wu)橡(xiang)(xiang)(xiang)(xiang)(xiang)胶(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)，全名(ming)为顺-1，4-聚(ju)异(yi)戊(wu)二烯(xi)橡(xiang)(xiang)(xiang)(xiang)(xiang)胶(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)，由(you)异(yi)戊(wu)二烯(xi)制(zhi)得(de)的(de)(de)(de)高顺式合(he)(he)成橡(xiang)(xiang)(xiang)(xiang)(xiang)胶(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)，因其(qi)(qi)结构和性(xing)(xing)(xing)能(neng)与天(tian)然(ran)(ran)橡(xiang)(xiang)(xiang)(xiang)(xiang)胶(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)近似，故又称(cheng)合(he)(he)成天(tian)然(ran)(ran)橡(xiang)(xiang)(xiang)(xiang)(xiang)胶(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)。③丁(ding)(ding)(ding)苯(ben)(ben)(ben)橡(xiang)(xiang)(xiang)(xiang)(xiang)胶(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)，简(jian)称(cheng)SBR，由(you)丁(ding)(ding)(ding)二烯(xi)和苯(ben)(ben)(ben)乙烯(xi)共聚(ju)制(zhi)得(de)。按生(sheng)产(chan)方法分为乳(ru)液(ye)聚(ju)合(he)(he)丁(ding)(ding)(ding)苯(ben)(ben)(ben)橡(xiang)(xiang)(xiang)(xiang)(xiang)胶(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)和溶液(ye)聚(ju)合(he)(he)丁(ding)(ding)(ding)苯(ben)(ben)(ben)橡(xiang)(xiang)(xiang)(xiang)(xiang)胶(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)。其(qi)(qi)综(zong)(zong)(zong)合(he)(he)性(xing)(xing)(xing)能(neng)和化(hua)学稳(wen)定性(xing)(xing)(xing)好(hao)(hao)。④顺丁(ding)(ding)(ding)橡(xiang)(xiang)(xiang)(xiang)(xiang)胶(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)，全名(ming)为顺式-1，4-聚(ju)丁(ding)(ding)(ding)二烯(xi)橡(xiang)(xiang)(xiang)(xiang)(xiang)胶(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)，简(jian)称(cheng)BR，由(you)丁(ding)(ding)(ding)二烯(xi)聚(ju)合(he)(he)制(zhi)得(de)。与其(qi)(qi)他通用(yong)(yong)(yong)型(xing)橡(xiang)(xiang)(xiang)(xiang)(xiang)胶(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)比，硫化(hua)后的(de)(de)(de)顺丁(ding)(ding)(ding)橡(xiang)(xiang)(xiang)(xiang)(xiang)胶(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)的(de)(de)(de)耐寒性(xing)(xing)(xing)、耐磨(mo)性(xing)(xing)(xing)和弹性(xing)(xing)(xing)特别优(you)异(yi)，动负荷下发热少，耐老化(hua)性(xing)(xing)(xing)能(neng)好(hao)(hao)，易与天(tian)然(ran)(ran)橡(xiang)(xiang)(xiang)(xiang)(xiang)胶(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)、氯丁(ding)(ding)(ding)橡(xiang)(xiang)(xiang)(xiang)(xiang)胶(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)、丁(ding)(ding)(ding)腈(jing)橡(xiang)(xiang)(xiang)(xiang)(xiang)胶(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)等并用(yong)(yong)(yong)。⑤氯丁(ding)(ding)(ding)橡(xiang)(xiang)(xiang)(xiang)(xiang)胶(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)(jiao)，简(jian)称(cheng)CR，由(you)氯丁(ding)(ding)(ding)二烯(xi)聚(ju)合(he)(he)制(zhi)得(de)。具有良好(hao)(hao)的(de)(de)(de)综(zong)(zong)(zong)合(he)(he)性(xing)(xing)(xing)能(neng)，耐油、耐燃(ran)、耐氧化(hua)和耐臭氧。但其(qi)(qi)密度(du)较大(da)，常温(wen)下易结晶变硬，贮(zhu)存(cun)性(xing)(xing)(xing)不(bu)好(hao)(hao)，耐寒性(xing)(xing)(xing)差。