天(tian)然樹(shu)脂是什么 樹(shu)脂分類與作用淺談

簡介

天(tian)然樹脂主要(yao)來源于植物滲（泌(mi)）出物的無定形半固(gu)體或固(gu)體有(you)(you)機物。受熱時變軟，并可熔化，在應力(li)作用下有(you)(you)流(liu)動的傾向，一般(ban)不(bu)溶于水(shui)，而能溶于醇、醚、酮(tong)及其他有(you)(you)機溶劑。

分類

這類物(wu)質種類繁多，來源(yuan)于植物(wu)者，主要有松香(xiang)、大漆、琥珀和?瑪樹脂(zhi)等；來源(yuan)于動物(wu)者，主要有蟲(chong)膠(jiao)，它是紫膠(jiao)蟲(chong)的分(fen)泌物(wu)。天(tian)然(ran)樹脂(zhi)可根據樹脂(zhi)組分(fen)、樹脂(zhi)形成的歷(li)史(shi)進(jin)行(xing)分(fen)類。

按照樹脂的基本組分可分為三大類：

①純樹脂，即(ji)由萜類物質(zhi)及粗香精油組成的樹脂狀物質(zhi)。一般不溶于(yu)水，而(er)溶于(yu)有機溶劑，如(ru)松香等。

②含樹膠脂或稱樹膠樹脂，是由多醣類物質組成，可(ke)溶于水或遇水溶脹，而不溶于醇(chun)及有機溶劑，如(ru)乳香等。

③含(han)(han)油樹(shu)(shu)脂(zhi)(zhi)(zhi)或稱(cheng)香(xiang)膠，是指含(han)(han)有(you)較多(duo)精(jing)油、能溶(rong)于(yu)油中的樹(shu)(shu)脂(zhi)(zhi)(zhi)。按樹(shu)(shu)脂(zhi)(zhi)(zhi)的形成歷史可分為化石樹(shu)(shu)脂(zhi)(zhi)(zhi)、半化石樹(shu)(shu)脂(zhi)(zhi)(zhi)和新鮮樹(shu)(shu)脂(zhi)(zhi)(zhi)。后者(zhe)是最重(zhong)要的天然樹(shu)(shu)脂(zhi)(zhi)(zhi)來源(yuan)。有(you)些(xie)天然樹(shu)(shu)脂(zhi)(zhi)(zhi)由最早集運出口的港口名稱(cheng)得(de)名，如瑪樹(shu)(shu)脂(zhi)(zhi)(zhi)、柯巴樹(shu)(shu)脂(zhi)(zhi)(zhi)等(deng)。

作用

天(tian)然(ran)(ran)(ran)樹脂主要用作(zuo)涂料(liao)（見天(tian)然(ran)(ran)(ran)樹脂涂料(liao)），也可用于造(zao)紙、絕緣材(cai)料(liao)、膠粘劑、醫(yi)藥(yao)、香料(liao)等的(de)生產過程；有(you)些可作(zuo)裝飾工藝(yi)品的(de)原料(liao)(如(ru)琥珀)；還有(you)的(de)如(ru)加(jia)拿大(da)膠，其折光(guang)指數與(yu)普通玻璃相似(si)，故作(zuo)為顯微鏡等光(guang)學器材(cai)的(de)透明膠粘劑。由于合成樹脂的(de)發展，天(tian)然(ran)(ran)(ran)樹脂的(de)應用日趨減(jian)少。

常見天然樹脂

松(song)(song)(song)(song)香(xiang)(xiang)(xiang)(xiang)。從松(song)(song)(song)(song)樹(shu)分(fen)泌的(de)(de)(de)粘稠(chou)液(ye)體中精制(zhi)而(er)(er)得(de)。是(shi)一(yi)種透明脆性(xing)的(de)(de)(de)固體物(wu)質(zhi)，顏(yan)色由微(wei)黃(huang)至(zhi)棕紅色。從其采集方法可(ke)分(fen)為脂松(song)(song)(song)(song)香(xiang)(xiang)(xiang)(xiang)和木松(song)(song)(song)(song)香(xiang)(xiang)(xiang)(xiang)。脂松(song)(song)(song)(song)香(xiang)(xiang)(xiang)(xiang)又(you)稱膠松(song)(song)(song)(song)香(xiang)(xiang)(xiang)(xiang)。從松(song)(song)(song)(song)香(xiang)(xiang)(xiang)(xiang)樹(shu)干上直接(jie)割口收集流出的(de)(de)(de)粘稠(chou)汁液(ye)，稱為毛松(song)(song)(song)(song)香(xiang)(xiang)(xiang)(xiang);蒸出松(song)(song)(song)(song)節油(you)(you)后，精制(zhi)便得(de)到成(cheng)品(pin)脂松(song)(song)(song)(song)香(xiang)(xiang)(xiang)(xiang)，其特點(dian)是(shi)顏(yan)色淺、酸值高、軟化(hua)(hua)點(dian)高。木松(song)(song)(song)(song)香(xiang)(xiang)(xiang)(xiang)是(shi)從殘留(liu)的(de)(de)(de)松(song)(song)(song)(song)香(xiang)(xiang)(xiang)(xiang)樁或樹(shu)根，經溶劑萃取、蒸餾(liu)分(fen)離揮發性(xing)油(you)(you)后而(er)(er)制(zhi)得(de)，質(zhi)量不如脂松(song)(song)(song)(song)香(xiang)(xiang)(xiang)(xiang)好(hao)。松(song)(song)(song)(song)香(xiang)(xiang)(xiang)(xiang)的(de)(de)(de)品(pin)質(zhi)由顏(yan)色、酸值、軟化(hua)(hua)點(dian)等(deng)(deng)的(de)(de)(de)不同而(er)(er)分(fen)級。松(song)(song)(song)(song)香(xiang)(xiang)(xiang)(xiang)中90％以上為各種同分(fen)異構的(de)(de)(de)松(song)(song)(song)(song)香(xiang)(xiang)(xiang)(xiang)酸，其余是(shi)這(zhe)些酸的(de)(de)(de)酯類和一(yi)些不皂(zao)(zao)化(hua)(hua)物(wu)。松(song)(song)(song)(song)香(xiang)(xiang)(xiang)(xiang)酸是(shi)一(yi)種弱酸，可(ke)以進行酯化(hua)(hua)、皂(zao)(zao)化(hua)(hua)等(deng)(deng)反應(ying)；對氧的(de)(de)(de)作用(yong)很敏感，氧化(hua)(hua)后使松(song)(song)(song)(song)香(xiang)(xiang)(xiang)(xiang)顏(yan)色變深，也能(neng)聚合成(cheng)二聚體；在(zai)250～260°C能(neng)受(shou)熱分(fen)解。松(song)(song)(song)(song)香(xiang)(xiang)(xiang)(xiang)主要(yao)用(yong)于肥皂(zao)(zao)、造紙等(deng)(deng)工(gong)業，制(zhi)成(cheng)各種加(jia)工(gong)產(chan)品(pin)如松(song)(song)(song)(song)香(xiang)(xiang)(xiang)(xiang)皂(zao)(zao)、松(song)(song)(song)(song)香(xiang)(xiang)(xiang)(xiang)酯等(deng)(deng)用(yong)于涂(tu)料工(gong)業。松(song)(song)(song)(song)香(xiang)(xiang)(xiang)(xiang)在(zai)中國產(chan)量很大，主要(yao)產(chan)于西南、華南地(di)區(qu)。

琥珀。松樹分(fen)泌的(de)(de)樹脂在地(di)下長(chang)期(qi)埋藏(zang)而得到的(de)(de)一(yi)種(zhong)化(hua)石樹脂，多用于珠寶、其他(ta)工藝品。

柯(ke)巴(ba)(ba)(ba)(ba)(ba)樹(shu)(shu)脂(zhi)(zhi)(zhi)和瑪樹(shu)(shu)脂(zhi)(zhi)(zhi)。從(cong)非洲(zhou)(zhou)和新(xin)西蘭(lan)等地的(de)(de)(de)(de)木(mu)本植物(wu)(wu)(wu)分泌物(wu)(wu)(wu)得(de)(de)到(dao)的(de)(de)(de)(de)一(yi)類樹(shu)(shu)脂(zhi)(zhi)(zhi)。根據產(chan)地和植物(wu)(wu)(wu)來源不同(tong)有(you)多種名稱，產(chan)于非洲(zhou)(zhou)的(de)(de)(de)(de)有(you)剛果柯(ke)巴(ba)(ba)(ba)(ba)(ba)、馬達(da)加(jia)斯加(jia)柯(ke)巴(ba)(ba)(ba)(ba)(ba)等，產(chan)于新(xin)西蘭(lan)的(de)(de)(de)(de)有(you)高(gao)里(li)柯(ke)巴(ba)(ba)(ba)(ba)(ba)等，產(chan)于菲律賓(bin)的(de)(de)(de)(de)有(you)馬尼拉柯(ke)巴(ba)(ba)(ba)(ba)(ba)等。從(cong)植物(wu)(wu)(wu)直接采取制(zhi)得(de)(de)的(de)(de)(de)(de)是(shi)軟(ruan)質柯(ke)巴(ba)(ba)(ba)(ba)(ba)，如馬尼拉柯(ke)巴(ba)(ba)(ba)(ba)(ba)；樹(shu)(shu)木(mu)分泌物(wu)(wu)(wu)長期埋藏(zang)于地下轉化(hua)而成(cheng)(cheng)化(hua)石樹(shu)(shu)脂(zhi)(zhi)(zhi)，是(shi)硬質柯(ke)巴(ba)(ba)(ba)(ba)(ba)或化(hua)石柯(ke)巴(ba)(ba)(ba)(ba)(ba)，如剛果柯(ke)巴(ba)(ba)(ba)(ba)(ba)等，采得(de)(de)的(de)(de)(de)(de)粗(cu)樹(shu)(shu)脂(zhi)(zhi)(zhi)經過精制(zhi)即(ji)得(de)(de)各種柯(ke)巴(ba)(ba)(ba)(ba)(ba)樹(shu)(shu)脂(zhi)(zhi)(zhi)。它們的(de)(de)(de)(de)軟(ruan)化(hua)點約在 100～300°C，多數(shu)約在150°C。柯(ke)巴(ba)(ba)(ba)(ba)(ba)樹(shu)(shu)脂(zhi)(zhi)(zhi)的(de)(de)(de)(de)主要成(cheng)(cheng)分為樹(shu)(shu)脂(zhi)(zhi)(zhi)酸，瑪樹(shu)(shu)脂(zhi)(zhi)(zhi)則是(shi)龍腦香科植物(wu)(wu)(wu)的(de)(de)(de)(de)分泌物(wu)(wu)(wu)。瑪樹(shu)(shu)脂(zhi)(zhi)(zhi)和柯(ke)巴(ba)(ba)(ba)(ba)(ba)樹(shu)(shu)脂(zhi)(zhi)(zhi)在19世紀為涂(tu)料(liao)的(de)(de)(de)(de)原料(liao)，現(xian)已(yi)幾乎不用(yong)。

蟲膠。也稱紫膠，是印度(du)、馬來西亞和中國(guo)云南等(deng)地產(chan)的(de)紫膠蟲，由(you)于新陳代謝作用(yong)，分(fen)泌出的(de)膠質(zhi)積累在樹(shu)枝上的(de)一種動(dong)物(wu)質(zhi)樹(shu)脂。從樹(shu)枝上剝取(qu)的(de)分(fen)泌物(wu)，經過精制即(ji)成為蟲膠片(pian)。蟲膠能溶于乙(yi)醇(chun)。現在在涂料(liao)工業中還有少量應(ying)用(yong)。