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Bacterial cellulose/polyaniline (BC/PANI) nanocomposites display many potential applications in various fields. However, the conductivity and mechanical properties remain a challenge. Here, we developed a novel method to prepare BC/PANI nanocomposites via the chemical grafting of PANI onto epoxy modified BC (EBC), followed by the grafting of polyacrylamide (PAM). For comparison, an in situ BC/PANI sample was also prepared. The grafting reaction between PANI and EBC and the retention of PANI on EBC were confirmed by FTIR, X-ray photoelectron spectroscopy, and elemental analysis. The cross-section morphology of BC transformed into a three-dimensional and continuous network structure with the incorporation of PANI. The effects of epoxy and PAM contents on the morphology, conductivity, and mechanical properties of PANI-g-EBC and PANI-g-EBC3/PAM nanocomposites were investigated. Compared with those of the in situ BC/PANI sample, the conductivity of PANI-g-EBC increased from 0.12 to 1.08 S/cm, while the stress increased from 8.18 to 18.47 MPa. With the addition of PAM, the conductivity of PANI-g-EBC/PAM nanocomposite paper further increased to 1.43 S/cm, and the stress increased to 47.94 MPa. The conductivity of PANI-g-EBC3/PAM nanocomposites only decreased from 1.43 to 1.36 S/cm after refolding 160 times. PANI-g-EBC and PANI-g-EBC3/PAM nanofibers could be blended with conventional plant cellulose fiber to prepare flexible and high strength conductive composite paper.

Cationic acetylated starch‐g‐poly(styrene‐butyl acrylate) surfactant‐free emulsion (CAS‐g‐poly(St‐BA)) was synthesized by graft copolymerization of styrene (St) and butyl acrylate (BA) onto CAS using FeSO4–H2O2 redox initiator. The maximum graft of 55.68% was derived when H2O2 concentration, monomer concentration, and St/BA ratio were 9%, 130%, and 1:1, respectively. The results obtained from FTIR, NMR (H1 NMR and C13 NMR), XRD, SEM, and thermogravimetric analysis (TGA‐DTG) confirmed graft copolymerization of St and BA onto CAS. And it was demonstrated that film‐forming properties of starch were greatly improved via grafting St and BA onto starch. It was also found that paper sized with CAS‐g‐poly(St‐BA) exhibited higher ring crush index and bursting strength than paper sized with cationic potato starch (CS) and CAS, as well as much lower water absorption, which is further verified by contact angles results.

Waterborne polyaniline (PANI) dispersion has got extensive attention due to its environmental friendliness and good processability, whereas the storage stability and mechanical property have been the challenge for the waterborne PANI composites. Here we prepare for waterborne PANI dispersion through the chemical graft polymerisation of PANI into epichlorohydrin modified poly (vinyl alcohol) (EPVA). In comparison with waterborne PANI dispersion prepared through physical blend and in situ polymerisation, the storage stability of PANI-g-EPVA dispersion is greatly improved and the dispersion keeps stable for one year. In addition, the as-prepared PANI-g-EPVA film displays more uniform and smooth morphology, as well as enhanced phase compatibility. PANI is homogeneously distributed in the EPVA matrix on the nanoscale. PANI-g-EPVA displays different morphology at different aniline content. The electrical conductivity corresponds to 7.3 S/cm when only 30% PANI is incorporated into the composites, and then increases up to 20.83 S/cm with further increase in the aniline content. Simultaneously, the tensile strength increases from 35 MPa to 64 MPa. The as-prepared PANI-g-EPVA dispersion can be directly used as the conductive ink or coatings for cellulose fibre paper to prepare flexible conductive paper with high conductivity and mechanical property, which is also suitable for large scalable production.

Functionalizing graphene with titanate coupling agents as reinforcement for one-Functionalizing graphene with titanate coupling agents as reinforcement for onecomponent waterborne poly(urethane-acrylate) anticorrosion coatings component waterborne poly(urethane-acrylate) anticorrosion coatings

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Waterborne UV-curable polyurethane (UWPU) dispersions with different hydrophilicity and functionalities were prepared by varying the content of dimethylol butanoic acid (DMBA) and pentaerythritol triacrylate (PETA). And linear and cyclic chain extenders with different functionalities were also incorporated into the UWPU backbone, including isophorone diamine (IPDA), diethylene triamine (DETA), and ethylene diamine (EDA). Effects of DMBA content, PETA content, photoinitiator content, UV curing time, chain extender on the properties of UWPU dispersions and films, as well as the properties of the unsized and sized paper were investigated. The water resistance and mechanical properties of sized paper were greatly relied on the particle size, the molecular weight, the croslinking density, and penetrability of UWPU. UWPU dispersion chain extended with IPDA (IPDA-UWPU) displayed smaller particle size than that of UWPU. The paper sized with IPDA-UWPU was endowed with best water resistance, tensile strength, folding strength and surface strength. XPS depth analysis revealed that IPDA-UWPU exhibited better penetrability into the paper substrate than UWPU. SEM and AFM demonstrated that the smoothness of sized paper was improved, and the bond strength between fibers was enhanced. The obtained UWPU could be directly used as an effective and fast drying surface sizing agent for cellulose fiber paper.