| 摘要: | 嵌段式聚氨基甲酸酯(Segmented Polyurethane，SPU)是一種團聯共聚物，本身的結構可分為兩大部分，分別是由多元醇所組成的軟質鏈段，及由二異氰酸酯與鏈延長劑所構成的硬質鏈段，由於兩大部分皆具有化學結構數目眾多特性，再加上不同的化學組成又會使兩鏈段之間產生不同的微相變化，所以使其擁有多變的化性及物性優勢。 本實驗室過去的研究中，為了瞭解巨大基團(Bulky diol)對嵌段性PU的影響，所以便於合成過程中，導入自行合成出的巨大基團來進行一系列的硬質鏈段改質，並對其進行一系列的深入研究。但由於巨大基團於反應時，是藉由兩末端的羥基(-OH)與二異氰酸酯反應，故其本身亦是鏈延長劑的一種，所以當巨大基團導入於反應中時，不僅會造成硬質鏈段於排列上的立體障礙，亦會延伸硬質鏈段的長度，進而影響硬質鏈段的排列，故以此觀點作為新的出發點，進行一系列的實驗與分析。 本實驗在合成過程中採用六種沒有支鏈的線性鏈延長劑，分別是EDO (Ethylene glycol)、PDO (1,3-Propanediol)、BDO (1,4-Butanediol)、PeDO (1,5-Pentanediol)、ODO (1,8-Octanediol)與NDO (1,9-Nonanediol)，至於二異氰酸酯則是使用MDI (4,4-diphenylmethane diisocyanate)，而多元醇則選用近非極性的polyesters polyols (Priplast1838)。在聚合過程中，將各別導入上述不同長度的線性雙醇來進行對硬質鏈段的改質，合成出一系列具有不同硬質鏈段長度與不同硬質鏈段段含量的非極性PU彈性體，並利用FT-IR、DMA、拉力測試、TGA、與DSC，探討PU於不同長度鏈延長劑的影響下所造成之性質與結構變化。 Segmented Polyurethane (SPU) is a kind of block copolymer , for the structure , we could separated into two parts . One is soft segment , build up by poliol ; the other is compose by diisocyanate and chain extender , called hard segment . Because both of these parts have the property of large number of chemical structures , the other hand , different chemical composition will make the difference result between the two segments of the micro-domain change , so it has advantages of many chemical and physical properties . Previous studies in our laboratory , in order to find the effective on bulky diol to segmented PU . We add in bulky diol which merge by ourselves for the series modify and further studies of hard segment . The reaction process of bulky diol also reaction by both ends of hydroxyl (-OH) and diisocyanate , we could identified a kind of chain extender . At the time we add bulky diol in reaction , not only lead the steric hindrance of arrangement , but also extend the length of hard segment . For this reason , we plan a series experiments for analysis . In this experiment , I used six kind of linear chain extenders without branched-chains follow : EDO (Ethylene glycol) , PDO (1,3-Propanediol) , BDO (1,4-Butanediol) , PeDO (1,5-Pentanediol) , ODO (1,8-Octanediol) and NDO (1,9-Nonanediol) . We selected MDI (4,4-diphenylmethane diisocyanate) and nearly nonpolar polyesters polyols (Priplast1838) for diisocyanate and polyol used . We will add the different length linear diol as above mentioned in polymerization process for modified hard segment , to produce a series nonpolar PU elastomer with different chain extender length and hard segment content . We also use FT-IR , DMA , tensile , TGA and DSC to study PU’s properties and structural changes under the effective of different length of chain extender . |
