Polyvinylamine (PVAm) was synthesized by Hofmann degradation of polyacrylamide (PAM). The thermal properties of the Polyvinylamine hydrochloride (PVAm•HCl) were studied by differential scanning calorimeter (DSC). The degradation rate (a) decreased with increasing weight-average molecular weight (Mw) of PAM and decreasing amount of NaOH, and a were the better values when the concentration of PAM was 5% and the amount of NaClO was 10 mL. DSC curves showed that the glass transition temperature (Tg) of PVAm•HCl increased with increasing Mw of PAM, concentration of NaClO and decreasing concentration of NaOH. Tg of PVAm•HCl appeared the minimum value when the concentration of PAM was 5.0%.

In this article, graft copolymerization of styrene (St) onto cassava starch via potassium diperiodatonickelate (IV)–starch redox system as an initiator was investigated in an alkaline medium. The effects of reaction variables were investigated, and the grafting conditions were optimized. The equation of the polymerization rate were obtained, Rp= k•C1.02 (St)•C0.53 (Ni（IV）). The graft copolymer was characterized with Fourier-transform infrared spectra analysis (FTIR) and scanning electron microscopy (SEM). FTIR spectra indicated the presence of PSt-g-starch copolymer. SEM micrographs also showed PSt adhering on the starch.

The AB2 type hyperbranched poly(amine ester) (HBPAE) can be used as adsorbent to adsorb nitrite from aqueous solution due to a large number of terminal hydroxyl groups, where the hydrogen-bonds could formed between OH and NO2-. However, the hydrophilic properties of HBPAE limited their utility in the application because of the difficulties in removing adsorbent from nitrite solution after the adsorption was finished. The hydrophilic properties of the HBPAE were changed by means of end capping method, where the trichloroctadecylsilan (OTS) was adopted as the hydrophobic alkyl chains. The modified HBPAE by OTS can be separated from the aqueous solution. The adsorption kinetics of nitrite from aqueous solutions onto modified HBPAE was investigated to show the pseudo-first-order kinetic mechanism. The equilibrium adsorption data were found to be well fitted by Freundlich isotherm equation.

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In this article, the graft copolymerization of 4-vinyl pyridine onto poly (ethylene terephthalate)(PET) via the potassium diperiodacuprate(III)–PET redox system as an initiator was investigated in an alkaline medium. The graft copolymer was characterized with Fourier-transform infrared spectra analysis. A mechanism is proposed to explain the generation of radicals and the initiation. The effects of reaction variables, such as the initiator concentration, the ratio of monomer to PET, pH, and reaction temperature and time, are investigated, and the grafting conditions are optimized. Graft copolymers with high grafting efficiency are obtained, thus indicating that potassium diperiodacuprate(III)-PET redox system is an efficient initiator for this graft copolymerization. The quaternized PET-g-PVP (QPEVP) is proved to be an excellent adsorbent to heavy metal ions.