带树枝状侧链聚苯乙炔的合成与结构表征  

SYNTHESIS AND CHARACTERIZATION OF A POLYPHENYLACETYLENE WITH DENDRON PENDANTS

作　　者：汪剑[1] 赵辉[1] 蔡春根[1] 毛宇[1] 唐莉[1] 沈晓源[1] 徐海鹏[1] 袁望章[1,2] 孙景志[1] 唐本忠[1,2] 

机构地区：[1]浙江大学高分子科学与工程学系大分子合成与功能构造教育部重点实验室,杭州310027 [2]香港科技大学化学系,中国香港

出　　处：《高分子学报》2009年第4期293-297,共5页Acta Polymerica Sinica

基　　金：国家自然科学基金(基金号20634020,50573065);国家重点基础研究发展计划(973计划,项目号2002CB613401)资助项目

摘　　要：合成了带树枝状聚苯甲醚修饰基团的苯乙炔单体,在Rh[(nbd)Cl2]2催化剂的作用下得到了侧链带聚苯甲醚树枝的新型聚苯乙炔衍生物,用红外吸收光谱、核磁共振谱、紫外可见吸收光谱和凝胶渗透色谱表征了聚合物的结构.发现聚合物的重均分子量达到了57300,在氯仿、N,N-二甲基甲酰胺、四氢呋喃等有机溶剂中有良好的溶解性能.由于侧链上聚苯甲醚树枝体积庞大,聚合物主链采取立构规整的顺-顺式构象,紫外可见吸收光谱在440nm附近出现了显著的共轭主链的吸收肩峰;立构规整的顺-顺式构象使树枝状侧链形成了对主链保护的"夹套效应",聚合物热分解温度从聚苯乙炔母体的225℃提高到295℃.Polymerization of a phenylacetylene monomer bearing a dendron moiety was carried out by using a rhodium complex Rh [ （nbd） C12 ] 2 as catalyst. The structure of the resultant was characterized with infrared （IR）, nuclear magnetic resonance （NMR）, and UV-Visible absorption spectroscopic techniques; the experimental data confirmed the generation of the expected polyphenylacetylene derivative （P1） with dendron pendants. P1 was soluble in common organic solvents such as chloroform, N, N-dimethylformamide oxide, and tetrahydrofurran （THF）, and its average molecular weight was about 57300. The steric repulsion of between the bulky dendritic side chains make the polymer main-chain take a stereoregular cis-cisoid conformation. Consequently, P1 exhibits a pronounced shoulder at around 440 nm in the absorption spectrum its THF solution. Meanwhile, the bulky dendrons around the polymer main-chain protect the main-chain from thermal-induced decomposition via the ＂jacket effect＂, thus P1 lost 5 % of its weight at a temperature of 295 ℃, which is about 70℃ higher than its parent polymer, or polyphenylacetylene.

关 键 词：官能化聚炔 树枝状聚合物 构象 稳定性 

分 类 号：O632.1[理学—高分子化学]