SINGLE IONIC CONDUCTI0N OF POLYSILOXANE CONTAINING PROPYLENE CARBONATE GROUP AND LITHIUM POLYMERIC SALTS

The polysiloxane containing propylene carbonate side group and several lithium poly-meric salts were synthesized. The structure were confirmed by IR, NMR and XPS. Theblending systems of polysiloxane containing propylene carbonate group with different lithiumpolymeric salts were studied by ion conductivity XPS and DSC. Different lithium poly-meric salts in the blending system lead to conductivity arranged in the following sequence:poly(lithium ethylenebenzene sulfonate methylsiloxane)>poly(lithium propionate methyl-siloxane)>poly(lithium propylsulfonate methylsiloxane)>poly(lithium styrenesulfonate).In the blending system the best single ion conductivity was close to 10^(-5) Scm^(-1) at roomtemperature. XPS showed that at low lithium salt concentration the conductivity increasedwith the increasing content of lithium salt, in consequence of the increase of free ion andsolvent separated ion pair. At high lithium salt concentration the free ion was absent andthe solvent-separated ion pair functioned as carrier.

Synthesis and Antibacterial Action of Poly(DMAEMA-BC) with Various Molecular Weights

Antibacterial polymers of dimethylaminoethyl methacrylate benzyl ammonium chloride（DMAEMA-BC） with various molecular weights（Mws） were prepared under controlling radical polymerization conditions. The Mws of these polymers were determined by means of static multiangle laser light scattering and viscosity method. A Mark-Houwink equation was established to be [η]=0.154M0.764 for the Mw evaluation of poly（DMAEMA-BC）s. The effects of the Mws of these poly（DMAEMA-BC）s on their antibacterial activities against E. coli and S. aureus were investigated by various methods including viable cell counting, electrical conductivity titration, intracellular constituent leakage tests and electron microscopy. Our results indicate that the antibacterial efficiency of DMAEMA-BC was significantly enhanced after the monomers were polymerized into a polymer and increased obviously with the Mws,as a result of the increase of charge density. Further investigation of the molecular basis underlying the anti-bacterial role of these polymers revealed that poly（DMAEMA-BC） promoted the release of potassium ion from the membrane of bacterial cells and the release increased significantly with the Mws of the polymers used.

Preparation and evaluation of bis(diallyl alkyl tertiary ammonium salt) polymer as a promising adsorbent for phosphorus removal

Problems associated with water eutrophication due to high phosphorus concentrations and related environmentally safe solutions have attracted wide attention.A novel bis(diallyl alkyl tertiary ammonium salt)polymer,particularly poly(N1,N1,N6,N6-tetraallylhexane-1,6-diammonium dichloride)(PTAHDADC),was synthesized and characterized by Fourier transform infrared spectroscopy,nuclear magnetic resonance,scanning electron microscopy,mercury intrusion method,and thermogravimetric analysis.The adsorption characteristics in phosphorus were evaluated in dilute solution,and the recycling properties of PTAHDADC were investigated.Results showed that PTAHDADC possessed macropores with a size distribution ranging from 30 to 130μm concentrating at 63μm in diameter and had 46.52%of porosity,excellent thermal stability below 530 K,and insolubility.PTAHDADC could effectively remove phosphorus at p H=7–11 and had a removal efficiency exceeding 98.4%at pH=10–11.The adsorption equilibrium data of PTAHDADC for phosphorus accorded well with the Langmuir and pseudo-second-order kinetic models.Maximum adsorption capacity was 52.82 mg/g at 293 K.PTAHDADC adsorbed phosphorus rapidly and reached equilibrium within 90 min.Calculated activation energy Eawas 15.18 k J/mol.PTAHDADC presented an excellent recyclability with only 8.23%loss of removal efficiency after five adsorption–desorption cycles.The morphology and structure of PTAHDADC slightly changed as evidenced by the pre-and post-adsorption of phosphorus,but the process was accompanied by the partial deprotonation of the(–CH2)3-NH+group of PTAHDADC.The adsorption was a spontaneous exothermic process driven by entropy through physisorption,electrostatic attraction,and ion exchange.Survey results showed that PTAHDADC was a highly efficient and fast-adsorbing phosphorus-removal material prospective in treating wastewater.