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Purpose The purpose of this paper is to develop non-leaching and eco-friendly antimicrobial waterborne polyacrylates with excellent antibacterial properties by grafting antibacterial vinyl monomer, glycidyl methacrylate (GMA) modified polyhexamethylene guanidine hydrochloride (PHMG). Design/methodology/approach PHMG of different molecular weights were modified by GMA to synthesize antibacterial vinyl monomer, GMA-modified PHMG (GPHMG). Different content and molecular weights of GPHMG were used to synthesize antimicrobial waterborne polyacrylates through emulsion polymerization. Findings The addition of GPHMG gained by modifying PHMG showed little influence on thermal stability of the films, but decreased the glass transition temperature(Tg). Meanwhile, the tensile strength decreased, while the breaking elongation increased. The antibacterial properties of the antibacterial films with different GPHMG contents were studied, when GPHMG content was around 0.9 Wt.%, antibacterial films showed excellent antibacterial activity (antibacterial rate >= 99.99 per cent). When weight content of GPHMG in the films remained constant, antibacterial property of films increased first and then decreased with the increase of molecular weight of GPHMG. The structural antibacterial polymer film had more perdurable antibacterial activity than the blended one. Research limitations/implications The grafting efficiency of GPHMG to antimicrobial waterborne polyacrylates could be further improved. Practical implications Antimicrobial waterborne polyacrylates with excellent antibacterial properties can be used to antibacterial coating and adhesive. Originality/value The antibacterial properties of films with different molecular weight of GPHMG were studied, and the durability and stability of antibacterial properties between structural antimicrobial films and blended antimicrobial films were also investigated by ring-diffusion method.

Stearic acid was applied to modify the VO2 nanopowders, and the influence of modified medium, dosage of modifier, amount of activator, time of modification on the surface modification effect were studied. The modification parameters such as modifying agent and the conditions were optimized. The changes of Surface groups, particle size and the lipophilic degree of the dispersion system of VO2 nanopowders before and after modified by the stearic acid were researched. The modification mechanism is chemical bonding, which is not physical adsorption. And then the stearic acid modified mechanism was established and applied to explain the the process of modification parameters optimization. The modification of VO2 nanopowders could be used in color nanometer energy-saving coating.

In this paper, the hollow polymer nanolatex microspheres with uniform size and good monodisperse made by in-situ polymerization with the method of encapsulation non-solvent,and the effect of crosslinking monomer (DVB) dosage in the shell on the morphology and opacity of the hollow polymer nanolatex microspheres were investigated by the characterization methods of particle size analysismeter, viscosity meter, acid value analysis, SEM, TEM and UV-Vis spectrophotometry. The results show that under the other conditions and MAA dosage of the shell unchanged, when the crosslinking monomer dosage of the shell was less than 15wt%, with the reduce of the crpsslinking monomer dosage in the shell, the strength of the shell of the hollow polymer nanolatex microspheres trends decrease, when pore-swelled, the hollow polymer nanolatex microspheres were easily cracked and collapsed; when the dosage was greater than 20wt%, with the increase of the crosslinking monomer dosage in the shell, the strength of the shell and particle size of the hollow polymer nanolatex microspheres trends increase and decrease respectively, it becomes difficult to swell; when the dosage is between 15-20wt%, the dry film of the emulsion containing the hollow polymer nanolatex microspheres obtained the the optimal opacity performance.