由脂肪族二酰胺二醇合成聚酯酰胺及表征

利用脂肪族二元酸酯与乙醇胺反应容易获得的对称二酰胺二醇,经缩聚合成聚酯酰胺预聚体,并针对端羧基和端羟基同时扩链来提高分子量,获得可生物降解的聚酯酰胺.首先将N,N′-二(2-羟乙基)草酰胺(HEOA)或N,N′-二(2-羟乙基)己二酰胺(HEHA)与己二酸和丁二醇缩聚,制备同时带有端羧基及端羟基的脂肪族聚酯酰胺预聚体,通过1,4-双(2-噁唑啉)苯及己二酰双己内酰胺混合扩链剂扩链,获得高分子量脂肪族聚酯酰胺,并通过红外、1H-NMR、DSC及TGA对其结构和热性能进行了表征.结果表明,预聚体在制备过程发生了一定的酯-酰胺交换反应;扩链后聚合物的熔点、熔融焓和热稳定性有所下降;但热稳定性仍接近或略高于聚己二酸丁二酯.

SYNTHESIS AND CHARACTERIZATION OF POLYESTERAMIDES DERIVED FROM ALIPHATIC DIESTERDIAMIDES

Polyesteramide (PEA(n,x /y))prepolymers with Mn from 4400 to 6400 were synthesized through melt polycondensation from adipic,butanediol and N,N'-bis(2-hydroxyethyl) oxalamide (0) or N,N'-bis(2-hydroxyethyl) adipamide ( 4 ) at different butanediol ( x) to bisamidediol ( y ) molar ratios. Chain extension reaction was performed with 2,2'-(1,4-phenylene)-bis(2-oxazoline) ( PBOX) and adipoyl biscaprolactamate (ABC)as combined chain extenders. High molecular weight PEA(n,x/y) with Mn up to 22500 and Mw up to 53100 was prepared. The PEA(n,x /y) prepolymers and the chain extended PEA(n,x /y) were characterized by FTIR and 1H-NMR spectroscopy,differential scanning calorimetry( DSC),and thermogravimetric analysis (TGA). 1H-NMR spectra revealed that during the preparation of the PEA(n,x/y) prepolymers,some esteramide exchange side reaction took place. DSC studies indicated that after chain extension the Tm and ΔHm of the polyesteramides decreased. TGA studies showed that after the chain extension,the thermal stability of the PEA(n,x /y)s slightly decreased,but still a little higher than that of poly(butylene adipate).