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In this study, the ability to remove methylene blue cation pigment using wood-plastic composite containing high density polyethylene and wood powder as a recycled material was studied. The effect of some important parameters such as pH, adsorbent amount and contact time were investigated. Adsorption efficiencies for methylene blue was maximized at alkaline pH. Adsorption capacity increased with increasing adsorbent amount and contact time. The value of R2 in Langmuir model was equal to 1 and the separation factor for 0.5 and 1 g of adsorbent were 0.09 and 0.1, respectively. Given that the methylene blue adsorption data were more consistent with the Langmuir isotherm model, it can be stated that the wood-plastic composite probably has uniform adsorption surfaces and the adsorption process occurred in homogeneous system on the adsorbent surface. Based on the results of this study, it was observed that this composite is a suitable adsorbent for removing methylene blue from aqueous solutions and used as a purifying agent in the decolorization of effluents containing pigments. This adsorbent is recyclable and is cost-effective to remove dye from textile industry wastewater.

In this study, three middle range α-olefin monomers including 1-hexene, 1-octene, and 1-decene were oligomerized using conventional AlCl3/H2O catalytic system. Molecular weight and microstructure of the oligomers were analyzed by GPC and 1HNMR, respectively. By 1HNMR spectra, both internal (CHR=CHR′ and CHR=CR′R′′) and external (CH2=CR′R′′) olefins containing di and tri-substituted C=C bonds were detected. After successful oligomerization, synthesized polyα-olefins underwent hydrogenation process using Pd(0)-Hal catalyst to yield synthetic oils of PHex, POct, and PDec, respectively and then completion of the hydrogenation was confirmed by 1HNMR spectroscopy. The microstructure of the synthesized oligomers was rationalized using the ratio under the peak of CH + CH2/CH3 hydrogens (S1/S2) in 1HNMR spectra and the degree of oligomerization obtained from Mn. According to the results, the best match between theoretical and real S1/S2 is obtained when considering double bond isomerization in the synthesized PAOs. By knowing PAO molecular weight, a relationship between monomer type and S1/S2 in the PAO homopolymers was detected. Our suggested methodology can be generalized to the unknown PAO homopolymers to unravel their monomer type by simple 1HNMR and GPC analyses.

Hydroxyl functionalized nano-sized POSS or ethyleneglycol as diol monomers was incorporated to hydroxyl-terminated polybutadiene (HTPBD) chain in the presence of fumaryl chloride as extender. Blue light photocrosslinking system based on camphorquinone (photoinitiator) and dimethylaminoethyl methacrylate (accelerator) was applied to cure these two synthesized fumarate based macromers. Self-crosslinkability of unsaturated macromers and also crosslinking in presence of a reactive diluent were investigated in absence and presence of 1,4-butanediol dimethacrylate, respectively. Finally, photocured samples were characterized by XRD, SEM, equilibrium swelling study, TGA, DMTA, AFM and cell culture. The results showed that incorporation of POSS nanoparticle into the polymer matrix with a perfect distribution and dispersion can enhance thermal stability, mechanical and biocompatibility properties which can prove a good potential of this in-situ photocrosslinkable nanohybrid in medical applications.

Hydrogenolysis of a series of model Ziegler–Natta (Z–N) catalysts to form Ti–H bond was studied within DFT. We focused our efforts on Ti species attached to the (110) lateral cut of MgCl2 which exist as different centres including Ti–C2H5, Ti–CH2CH(CH3)2, and Ti–CH(CH3)CH2CH3 in ethylene and propylene polymerization. In the next step, reactivity of Ti–H bond towards ethylene and propylene (1,2- and 2,1-) insertion was investigated. Results showed that insertion of ethylene and propylene into Ti–H bond has less barrier, in comparison with their insertion in Ti–C bond, however, ethylene and propylene 2,1- insertion lead to Ti–C2H5 and Ti–CH(CH3)2 centres respectively, which were stable due to strong β-agostic interactions. Finally, by considering different possible reactions of active centre, activity depression in ethylene polymerization and activity increase in propylene polymerization were explained in detail.