李妍 顧紹興 王明明 羅根祥 安會(huì)勇



摘 要:采用低溫熔融法制備不溶性硫磺,并采用氣化溫度低、氣化潛力大的無水乙醇/干冰作為淬冷劑。比較了水和無水乙醇/干冰作為淬冷劑對(duì)不溶性硫磺的淬冷效果,研究了無水乙醇/干冰的溫度和用量對(duì)不溶性硫磺的淬冷效果的影響。實(shí)驗(yàn)結(jié)果表明,無水乙醇/干冰的淬冷效果好于水。溫度為-30 oC的無水乙醇/干冰,硫磺(g):無水乙醇(mL)=1:10(質(zhì)量:體積)的淬冷效果最好,120 oC /15 min的熱穩(wěn)定到達(dá)40.84%。通過DSC實(shí)驗(yàn)測(cè)出不溶性硫磺的熔點(diǎn)為124.68 oC。通過XRD譜圖證明合成的為不溶性硫磺。
關(guān) 鍵 詞:不溶性硫磺;淬冷;熱穩(wěn)定性;轉(zhuǎn)化率
中圖分類號(hào):TQ 028 文獻(xiàn)標(biāo)識(shí)碼: A 文章編號(hào): 1671-0460(2015)09-2084-04
Abstract: Insoluble sulfur was prepared by low temperature melting method with the mixture of anhydrous alcohol and dry ice as quenching agent. Quenching effects of water and the mixture of anhydrous alcohol and dry ice as quenching agent for insoluble sulfur were compared; effect of temperature and content of the mixture of anhydrous alcohol and dry ice on quenching effect for insoluble sulfur was investigated. The results show that quenching effect of the mixture of anhydrous alcohol and dry ice is better than that of water. When the temperature is -30 oC, sulfur(g): anhydrous alcohol/dry ice(mL)=1:10,the best quenching effect can be obtained. The maximum thermal stability of insoluble sulfur can reach to 40.84% under the condition of constant 120 oC for 15 min. Melting point of IS is 124.68 oC.
Key words: insoluble sulfur; quenching; thermal stability; conversion
不溶性硫磺(IS, Insoluble Sulfur)是具有不溶于二硫化碳和橡膠性質(zhì)的硫原子均聚物,也稱聚合硫和μ硫,屬于硫的一種同素異形體。不溶性硫磺外觀為黃色無毒可燃的粉末,密度為1.95 g/cm3,可通過高溫氣化法和低溫熔融法制備,是一種硫磺改性產(chǎn)品,可替代單質(zhì)硫磺用作高效橡膠硫化劑,分為未充油型和充油型兩類。
利用硫磺開環(huán)聚合方法,制備高品質(zhì)的不溶性硫磺需經(jīng)過以下生產(chǎn)工藝過程:開環(huán)聚合→淬冷→固化→萃取提純→充油。其中,淬冷過程是合成不溶性硫磺工藝至關(guān)重要的一步,淬冷效果對(duì)于不溶性硫磺的性能起著決定性的作用。按冷卻介質(zhì)種類,可將淬冷過程分為水介質(zhì)淬冷法(濕法)和非水淬冷法(干法)[1]。水介質(zhì)淬冷法是把一定量的穩(wěn)定劑水溶液作為淬冷介質(zhì)進(jìn)行淬冷的方法。非水介質(zhì)淬冷法是把含有穩(wěn)定劑的非水溶液或/和以低溫惰性氣體作為淬冷介質(zhì)進(jìn)行淬冷的方法?!?br>