A novel self-emulsifiable waterborne amine-terminated curing agent for epoxy resin based on glycidyl tertiary carboxylic ester (GTCE) was synthesized through three steps of addition reaction, capping reaction, and salification reaction of triethylene tetramine (TETA) and liquid epoxy resin (E-44). The curing agent with good emulsifying and curing properties was gradually obtained under condition of the molar ratio of TETA: E-44 as 2.2: 1 at 65 8C for 4 h, 100% primary amine capped with GTCE at 70 8C for 3 h, and 20% salifiable rate with glacial acetic acid. The curing agent was characterized by Fourier transform-infrared spectroscopy (FT-IR). The curing behavior of the E-44/GTCE-TETA-E-44 system was studied with differential scanning calorimetry (DSC) and FT-IR. Results showed that the optimal mass ratio for E-44/GTCE-TETA-E-44 system was 3 to 1, and the curing agent showed a relatively lower curing temperature. The cured film prepared by the self-emulsifiable curing agent and epoxy resin under the optimal mass ratio displayed good thermal property, hardness, toughness, adhesion, and corrosion resistance. V C 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44246.

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Some special oral drugs may cause adverse reactions and degrade in the stomach; therefore, it is necessary to develop a new generation of multifunctional drug delivery carries to deal with such issues. Herein, by polyelectrolyte composite method using KGM and CS as raw material, CKGM/CS/TPP/5‐ASA microcapsules are prepared using 5‐ASA as model drug, and then coated with an acid‐resistant polyacrylic acid polymer layer. The size of CKGM/CS/TPP/5‐ASA microcapsules is relatively uniform, with average particle size 1.78 ± 0.02 mm. The inner part of microcapsules has a core‐shell three‐dimensional network structure, and the 5‐ASA embedded in the network is in its crystal form. The microcapsules exhibited good encapsulate properties, with 495.5 µg mg−1 drug loading amount and 82.3% encapsulation efficiency under optimized conditions. The in vitro release properties of microcapsules are also studied, and results showed that the drug is released little in Simulated Gastric Fluid solution (pH 1.2) but fully released in Simulated Colonic Fluid or Phosphate Buffered Solution (pH 7.0), and the release rate is higher in SCF solution, indicating that β‐mannanase could facilitate release. All these results indicated that CKGM/CS/TPP microcapsules have good pH‐controlled release, enzymatic release, and sustained release properties, hence they are promising multifunctional colon‐targeted release carriers.