天然樹(shu)脂是(shi)什么(me) 樹(shu)脂分(fen)類與(yu)作用淺談

簡介

天然(ran)樹脂主要來源于(yu)植物(wu)滲(shen)（泌）出物(wu)的無定形半固(gu)體或(huo)固(gu)體有機物(wu)。受(shou)熱時變軟，并可熔化，在應力作用(yong)下有流(liu)動的傾向，一般不溶于(yu)水，而(er)能(neng)溶于(yu)醇、醚、酮及其他有機溶劑。

分類

這類(lei)物(wu)質種類(lei)繁多，來源(yuan)于植(zhi)物(wu)者(zhe)，主要有松香、大漆(qi)、琥珀和?瑪(ma)樹脂等；來源(yuan)于動物(wu)者(zhe)，主要有蟲膠(jiao)，它(ta)是紫膠(jiao)蟲的分(fen)泌物(wu)。天然樹脂可根據樹脂組分(fen)、樹脂形成的歷史進(jin)行分(fen)類(lei)。

按照樹脂的基本組分可分為三大類：

①純樹脂(zhi)，即由萜類物質(zhi)及粗香精油組(zu)成的樹脂(zhi)狀物質(zhi)。一般不(bu)溶于水，而(er)溶于有(you)機溶劑，如松香等。

②含樹(shu)膠脂(zhi)或稱樹(shu)膠樹(shu)脂(zhi)，是由多醣類物質組成，可(ke)溶(rong)于水或遇(yu)水溶(rong)脹，而不溶(rong)于醇及有機溶(rong)劑，如(ru)乳香等。

③含油樹(shu)(shu)(shu)(shu)脂(zhi)或稱香膠，是(shi)指含有較(jiao)多精油、能(neng)溶(rong)于(yu)油中的(de)樹(shu)(shu)(shu)(shu)脂(zhi)。按樹(shu)(shu)(shu)(shu)脂(zhi)的(de)形(xing)成歷史可分為化石(shi)樹(shu)(shu)(shu)(shu)脂(zhi)、半化石(shi)樹(shu)(shu)(shu)(shu)脂(zhi)和新鮮(xian)樹(shu)(shu)(shu)(shu)脂(zhi)。后者是(shi)最重要的(de)天(tian)然(ran)樹(shu)(shu)(shu)(shu)脂(zhi)來(lai)源。有些(xie)天(tian)然(ran)樹(shu)(shu)(shu)(shu)脂(zhi)由最早集運(yun)出口(kou)的(de)港(gang)口(kou)名稱得名，如瑪樹(shu)(shu)(shu)(shu)脂(zhi)、柯(ke)巴樹(shu)(shu)(shu)(shu)脂(zhi)等。

作用

天(tian)(tian)(tian)然(ran)樹脂(zhi)(zhi)主(zhu)要用作(zuo)涂料（見天(tian)(tian)(tian)然(ran)樹脂(zhi)(zhi)涂料），也可用于(yu)(yu)造紙、絕緣材料、膠(jiao)粘(zhan)劑(ji)、醫藥(yao)、香料等的生產過程；有些可作(zuo)裝(zhuang)飾工藝品(pin)的原料(如琥珀)；還(huan)有的如加拿大膠(jiao)，其折(zhe)光指數與普通玻(bo)璃相似，故作(zuo)為顯微鏡等光學器材的透(tou)明膠(jiao)粘(zhan)劑(ji)。由(you)于(yu)(yu)合成樹脂(zhi)(zhi)的發展(zhan)，天(tian)(tian)(tian)然(ran)樹脂(zhi)(zhi)的應(ying)用日趨減(jian)少(shao)。

常見天然樹脂

松(song)(song)(song)香(xiang)。從(cong)(cong)(cong)松(song)(song)(song)樹分(fen)(fen)泌的(de)(de)(de)(de)粘稠(chou)液體(ti)中(zhong)精制(zhi)而(er)得(de)。是一種透明脆性(xing)的(de)(de)(de)(de)固體(ti)物質(zhi)，顏(yan)(yan)色由微黃至(zhi)棕紅(hong)色。從(cong)(cong)(cong)其采集方法可分(fen)(fen)為(wei)(wei)脂松(song)(song)(song)香(xiang)和木松(song)(song)(song)香(xiang)。脂松(song)(song)(song)香(xiang)又稱(cheng)膠松(song)(song)(song)香(xiang)。從(cong)(cong)(cong)松(song)(song)(song)香(xiang)樹干(gan)上(shang)直接割口收(shou)集流(liu)出的(de)(de)(de)(de)粘稠(chou)汁液，稱(cheng)為(wei)(wei)毛松(song)(song)(song)香(xiang);蒸出松(song)(song)(song)節油后，精制(zhi)便得(de)到成(cheng)(cheng)品(pin)脂松(song)(song)(song)香(xiang)，其特點是顏(yan)(yan)色淺(qian)、酸值(zhi)高、軟化點高。木松(song)(song)(song)香(xiang)是從(cong)(cong)(cong)殘留的(de)(de)(de)(de)松(song)(song)(song)香(xiang)樁或樹根，經溶(rong)劑萃取(qu)、蒸餾分(fen)(fen)離揮發(fa)性(xing)油后而(er)制(zhi)得(de)，質(zhi)量不如脂松(song)(song)(song)香(xiang)好。松(song)(song)(song)香(xiang)的(de)(de)(de)(de)品(pin)質(zhi)由顏(yan)(yan)色、酸值(zhi)、軟化點等(deng)(deng)的(de)(de)(de)(de)不同(tong)而(er)分(fen)(fen)級(ji)。松(song)(song)(song)香(xiang)中(zhong)90％以(yi)上(shang)為(wei)(wei)各種同(tong)分(fen)(fen)異(yi)構的(de)(de)(de)(de)松(song)(song)(song)香(xiang)酸，其余是這些酸的(de)(de)(de)(de)酯類和一些不皂(zao)化物。松(song)(song)(song)香(xiang)酸是一種弱酸，可以(yi)進行酯化、皂(zao)化等(deng)(deng)反應；對氧的(de)(de)(de)(de)作用(yong)很(hen)敏感，氧化后使松(song)(song)(song)香(xiang)顏(yan)(yan)色變深(shen)，也能聚合成(cheng)(cheng)二聚體(ti)；在250～260°C能受熱分(fen)(fen)解。松(song)(song)(song)香(xiang)主(zhu)要用(yong)于(yu)肥皂(zao)、造紙等(deng)(deng)工業，制(zhi)成(cheng)(cheng)各種加工產(chan)品(pin)如松(song)(song)(song)香(xiang)皂(zao)、松(song)(song)(song)香(xiang)酯等(deng)(deng)用(yong)于(yu)涂(tu)料(liao)工業。松(song)(song)(song)香(xiang)在中(zhong)國產(chan)量很(hen)大，主(zhu)要產(chan)于(yu)西(xi)南(nan)、華南(nan)地(di)區(qu)。

琥珀。松樹分泌的(de)樹脂在(zai)地下長期埋藏而得到的(de)一(yi)種化石樹脂，多用于珠寶、其他工藝品。

柯(ke)(ke)巴(ba)(ba)(ba)(ba)(ba)樹(shu)(shu)脂(zhi)(zhi)和瑪樹(shu)(shu)脂(zhi)(zhi)。從非(fei)洲和新(xin)西(xi)蘭等(deng)(deng)(deng)地的(de)(de)(de)(de)木本植(zhi)物(wu)分泌(mi)物(wu)得(de)到的(de)(de)(de)(de)一類樹(shu)(shu)脂(zhi)(zhi)。根據產地和植(zhi)物(wu)來源不同有多(duo)(duo)種名稱，產于(yu)(yu)非(fei)洲的(de)(de)(de)(de)有剛果(guo)柯(ke)(ke)巴(ba)(ba)(ba)(ba)(ba)、馬(ma)達加(jia)斯加(jia)柯(ke)(ke)巴(ba)(ba)(ba)(ba)(ba)等(deng)(deng)(deng)，產于(yu)(yu)新(xin)西(xi)蘭的(de)(de)(de)(de)有高里柯(ke)(ke)巴(ba)(ba)(ba)(ba)(ba)等(deng)(deng)(deng)，產于(yu)(yu)菲(fei)律賓的(de)(de)(de)(de)有馬(ma)尼拉(la)柯(ke)(ke)巴(ba)(ba)(ba)(ba)(ba)等(deng)(deng)(deng)。從植(zhi)物(wu)直接(jie)采(cai)取制得(de)的(de)(de)(de)(de)是軟質柯(ke)(ke)巴(ba)(ba)(ba)(ba)(ba)，如馬(ma)尼拉(la)柯(ke)(ke)巴(ba)(ba)(ba)(ba)(ba)；樹(shu)(shu)木分泌(mi)物(wu)長期埋藏(zang)于(yu)(yu)地下(xia)轉化而成(cheng)化石(shi)樹(shu)(shu)脂(zhi)(zhi)，是硬質柯(ke)(ke)巴(ba)(ba)(ba)(ba)(ba)或化石(shi)柯(ke)(ke)巴(ba)(ba)(ba)(ba)(ba)，如剛果(guo)柯(ke)(ke)巴(ba)(ba)(ba)(ba)(ba)等(deng)(deng)(deng)，采(cai)得(de)的(de)(de)(de)(de)粗樹(shu)(shu)脂(zhi)(zhi)經(jing)過精制即得(de)各種柯(ke)(ke)巴(ba)(ba)(ba)(ba)(ba)樹(shu)(shu)脂(zhi)(zhi)。它們(men)的(de)(de)(de)(de)軟化點約在(zai) 100～300°C，多(duo)(duo)數約在(zai)150°C。柯(ke)(ke)巴(ba)(ba)(ba)(ba)(ba)樹(shu)(shu)脂(zhi)(zhi)的(de)(de)(de)(de)主(zhu)要(yao)成(cheng)分為樹(shu)(shu)脂(zhi)(zhi)酸，瑪樹(shu)(shu)脂(zhi)(zhi)則是龍腦香科植(zhi)物(wu)的(de)(de)(de)(de)分泌(mi)物(wu)。瑪樹(shu)(shu)脂(zhi)(zhi)和柯(ke)(ke)巴(ba)(ba)(ba)(ba)(ba)樹(shu)(shu)脂(zhi)(zhi)在(zai)19世紀為涂(tu)料的(de)(de)(de)(de)原料，現已幾乎不用。

蟲(chong)膠(jiao)(jiao)。也(ye)稱(cheng)紫膠(jiao)(jiao)，是印度、馬來西(xi)亞和中國云南(nan)等地產(chan)的紫膠(jiao)(jiao)蟲(chong)，由于新(xin)陳(chen)代謝作用，分泌(mi)出的膠(jiao)(jiao)質積累在(zai)樹枝(zhi)上的一(yi)種動物(wu)質樹脂(zhi)。從樹枝(zhi)上剝取的分泌(mi)物(wu)，經過精(jing)制即(ji)成為蟲(chong)膠(jiao)(jiao)片。蟲(chong)膠(jiao)(jiao)能(neng)溶于乙醇。現(xian)在(zai)在(zai)涂料工業(ye)中還(huan)有(you)少(shao)量(liang)應用。