During the preparation of UPR from dicyclopentadiene, the following two reactions occur:

　　1.二醇- alder反應(yīng):在160—170℃下，二環(huán)戊二烯分解成環(huán)戊二烯(CPD)， CPD在170℃以上與山東馬來酸酐反應(yīng)，然后與二元醇、二元酸酯化反應(yīng)。這種方法也稱為“酸酐法”。也可以將山東馬來酸酐與二元醇酯化制備單酯，在170 ~ 175℃條件下加入二環(huán)戊二烯，在200℃條件下完成酯化反應(yīng)。

　　1. Diol alder reaction: at 160-170 ℃, dicyclopentadiene decomposes into cyclopentadiene (CPD), which reacts with Shandong maleic anhydride above 170 ℃, and then esterifies with diol and dicarboxylic acid. This method is also known as the "acid anhydride method". Shandong maleic anhydride and diol can also be esterified to prepare monoester. Dicyclopentadiene can be added at 170 ~ 175 ℃, and esterification can be completed at 200 ℃.

　　2. 二環(huán)戊二烯的直接加成:后來發(fā)現(xiàn)，在酸的催化作用下，可以將醇或酸直接加到二環(huán)戊二烯的雙鍵上，形成醚或酯。這種直接加成反應(yīng)可以通過以下四種方式進(jìn)行:

　　2. Direct addition of dicyclopentadiene: it was later found that under the catalysis of acid, alcohol or acid can be directly added to the double bond of dicyclopentadiene to form ether or ester. The direct addition reaction can be carried out in the following four ways:

　　(1)初始方法:將山東馬來酸酐、鄰苯二酸酐、二醇、二環(huán)戊二烯全部放入反應(yīng)器中，加熱150℃，回流反應(yīng)30-60分鐘，再轉(zhuǎn)為縮合，加熱200℃完成酯化。

　　(1) Initial method: put Shandong maleic anhydride, phthalic anhydride, diol and dicyclopentadiene into the reactor, heat to 150 ℃, reflux reaction for 30-60 minutes, then convert to condensation, heat to 200 ℃ to complete esterification.

　　(2)水解法:先將山東馬來酸酐在等摩爾水中加熱80-100℃轉(zhuǎn)化為馬來酸酐，再降二環(huán)戊二烯快速完成反應(yīng)。然后加入二元醇和改性酸，在200℃下完成酯化反應(yīng)。

　　(2) Hydrolysis method: firstly, Shandong maleic anhydride is heated to 80-100 ℃ in equimolar water to be converted into maleic anhydride, and then dicyclopentadiene is reduced to complete the reaction quickly. After that, diol and modified acid were added and esterification was completed at 200 ℃.

　　(3)“半酯”法:先在150℃下由蝶齒酸酐與二元醇反應(yīng)，再由蝶齒酸酐環(huán)化。然后，在150℃下，通過滴注二環(huán)戊二烯的方式，對(duì)蝶閥戊二烯雙鍵上的羥基進(jìn)行醚化或?qū)Φy戊二烯雙鍵上的羧基進(jìn)行酯化。，酯化在200℃下完成。

　　(3) "Half ester" method: the reaction of diehydric anhydride with diol at 150 ℃, followed by cyclization of diehydric anhydride. Then, at 150 ℃, the hydroxyl group on the double bond of butterfly valve was etherified or the carboxyl group on the double bond of butterfly valve was esterified by dropping dicyclopentadiene. Finally, esterification was completed at 200 ℃.

　　(4)封端方法:在200℃下完成山東馬來酸酐、鄰苯二酸酐和二醇的酯化。當(dāng)酸降低到較低的值時(shí)，反應(yīng)冷卻到160℃，加入人體雙環(huán)戊二烯，封閉其端羥基和端基。

　　(4) Sealing method: the esterification of Shandong maleic anhydride, phthalic anhydride and diol was completed at 200 ℃. When the acid is reduced to a lower value, the reaction is cooled to 160 ℃, and dicyclopentadiene is added to block the end group and hydroxyl group.

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