摘要
采用玉米支链淀粉为主链,引入含有酰胺基团和磺酸基团的单体,在水溶液中聚合成一种新型改性淀粉类内养护剂(简称MC-ICA)。利用FITR、XRD、SEM和TG等表征MC-ICA的组成、结构和热稳定性能。分析表明:接枝聚合形成的MC-ICA中O-H、C-O间形成大量氢键,亲水性高;是一种非晶态、热稳定性好的共聚物。MC-ICA的吸水率较高,尤其是在近似水泥浆体孔溶液体系的吸水率是市售内养护剂的2倍。
A new type of modified corn starch internal curing agent(for short MC-ICA) was synthesized using aqueous polymerization method,which selects corn branched starch as the main chain,amide-group and sulfonic acid group as co-monomers.The molecular composition,structure and thermal stability of MC-ICA were characterized by Fourier transform infrared spectroscopy,X-ray diffraction,Scanning electron microscopy and thermal gravimetric.The results indicated that the a large number of hydrogen bonds are formed between O-Hand C-O in MC-ICA,which is an amorphous copolymer with high hydrophilicity and good thermal stability.MC-ICA has a high water absorption rate,especially in the slurry pore solution system which is similar to cement body,the water absorption rate is twice that of the market curing agent.
引文
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