Abstract:Diglyceride borate was successfully prepared from boric acid and glycerol by clean and efficient microwave esterification. Then glycerol propylene borate was synthesized successfully from glycerol borate and acryloyl chloride. Boron sustainedrelease super absorbent resin with hydroxypropyl methyl cellulose (HPMC) as the framework was successfully prepared using propylene glycerol borate as the functional monomer containing boron. At the same time, the water absorption ratio, water absorption rate, water holding capacity, structure and morphology of the product were characterized. From the results of infrared spectra, it can be seen that glycerol propylene borate with double bond structure was successfully prepared and boroncontaining super absorbent resin was successfully synthesized by graft copolymerization. The results showed that with the increase of boron-containing functional monomers, the absorption ratio of boroncontaining HPMC superabsorbent resin was decreased gradually. When the addition of boroncontaining functional monomers was 1% of the mass of acrylic acid, the water absorption ratio of HPMC boroncontaining super absorbent resin was 344.06g/g and the salt absorption ratio was 44.71g/g. When the amount of boroncontaining functional monomers was 5% of the mass of acrylic acid, the water absorption ratio of HPMC boron-containing super absorbent resin was decreased to 213.69g/g and the salt absorption ratio was decreased to 26.03g/g. The super absorbent resin had good water retention and could hold water for more than 72h at 35℃. The super absorbent resin had good water retention. The water retention rate could still reach 23.46% after 72h of water absorption to saturation at 35℃. The super absorbent resin had good reusability. After 6 times of reuse, the repetitive absorbent water could still reach more than 60% and the repetitive salt absorption rate could still reach more than 40%. The super absorbent resin had good sustained-release property of boron, and it could sustainably release boron in deionized water for 10d. The sustained release amount of boron reached 182.77μg. It could sustainably release boron in seedling matrix for more than 25d. When the addition amount was 0.5% of the quality of seedling matrix, boron leaching from mixed substrates was 0.80μg/g more than that from common substrates. In addition, HPMC boron-containing super absorbent resin also had good thermal stability, and its morphological characteristics were conducive to promoting the absorption of liquids.