Application of Et_3NHCl-AlCl_3 Ionic Liquid as an Initiator in Cationic Copolymerization of 1, 3-Pentadiene with Styrene

The random copolymer poly （1, 3-pentadiene-co-styrene） formed through cationic copolymerization using the ~ethylamine hydrochloride and hydrous aluminium chloride （Et3NHCl-AlCl3） room temperature ionic liquid as initiating agent in toluene was analyzed using IR spectra in conjunction with gel permeation chromatography （GPC）. The room temperature ionic liquid was found to have high initiatic activity for copolymerization.

Adsorption of cationic copolymer nanoparticles onto bamboo fiber surfaces measured by conductometric titration

Monosized nanoparticles of 57.3 nm were prepared by cationic emulsion polymerization using a polymerizable emulsifier DMHB.The adsorption of nanoparticles onto bamboo fibers was measured by conductometric titration.The results indicated that the adsorption capacity increased with increasing contact time until 120 min.The equilibrium data for nanoparticles adsorption onto bamboo fibers were well fitted to the Langmuir equation.Moreover,the monolayer adsorption capacity of nanoparticles in the concentration range（from 0.03 g/L to 0.6 g/L） studied,as calculated from Langmuir isotherm model at 25 C,was found to be 38.61 mg/g of fibers.The SEM images showed that the nanoparticles form a uniform monolayer on bamboo fiber surfaces.

STUDY ON CATIONIC RING-OPENING COPOLYMERIZATION OF 1,4-ANHYDRO-2,3-DI-O-BENZYL-α-D-RIBOPYRANOSE WITH 1,4-ANHYDRO-2,3-O-ISOPROPYLIDENE-α-D-RIBOPYRANOSE

Cationic ring-opening copolymerization of 1, 4-anhydro-2, 3-O-isopropylidene-α-D-ribo-pyranose (AIRP) with 1,4-anhydro-2,3-di-O-benzyl-α-D-ribopyranose (ADBR) preparedfrom D-ribose was studied. Copolymerization using SbCl_5 or BF_3 OEt_2 as catalyst atlow temperature gave stereoregular (1→4)β-D-ribofuranan (C-1 and C-4 ring cleavagesee Scheme 1) or (1→5) α-D-ribofuranan (C-1 and C-5 ring cleavage) respectively. Theeffects of catalysts, reaction time and temperatures on yield and stereoregularity of the ob-tained polymers were studied. Polymers were characterized by molecular weight, ~1HNMR,^(13)CNMR and optical rotation.

Optical Measurements to Reveal Roles of Slightly Crosslinked Poly (dimethyldiallylammonium chloride) s in Fixing Anionic Dyes on Cotton Fabric

The roles of slightly crosslinked poly( dimethyldiallylammonium chloride) s( PDMDAACs) in fixing anionic dyes on cotton fabric were verified more precisely by optical analysis technologies,to achieve the new theoretical guides for the widely applications. Firstly,one method of optical CIELAB color difference analysis was designed to exactly measure the values of dyefixing performances, so that the suitable molecular weights and structures of the slightly crosslinked PDMDAACs could be precisely confirmed to play a role in the development of their dye-fixing performances. Secondly,the FT-IR absorption shift of the dye on dyed cotton sample fixed by slightly crosslinked PDMDAACs was nearly in agreement with that of forming water-insoluble color lakes,indicating that the expected color lakes could be formed on dyed cotton fabric,and would play a role in further development of the fastness of dyes on cotton fabric. Thirdly,the FT-IR spectra of fixed undyed cotton samples and that of fixed dyed cotton samples both showed the absorptions of slightly crosslinked PDMDAACs,further revealing that the slightly crosslinked PDMDAACs could be penetrated into cotton fabric and be convenient to interact with dyes when fixing. However,those absorptions of the slightly crosslinked PDMDAACs fixed on cotton samples would be absent after being adequately washed to a constant weight,suggesting that the fixing interactions of the slightly crosslinked PDMDAAC and cotton fabric were very weak.

A novel approach for Apocynum venetum/cotton blended fabrics modification by cationic polymer nanoparticles

Apocynum venetum/cotton blended fabrics have been subjected to treat with cationic polymer nanoparticles followed by dyeing with Acid Red B,and then studied for their dyeing performance and morphology.The investigation on the effect of modification factors on the blended fabrics indicated that the 0.5 g/L nanoparticles concentration,60 min treating time,60 ℃ treating temperature and pH 6-8 are the optimum modification process to improve the dyeability of acid dye.In addition,the SEM images show that nanoparticles can be adsorbed on the surface of modified A.venetum or cotton fibers,and the two different fibers could have the same adsorption ability to Acid Red B.

Antibacterial and pH-responsive Quaternized Hydroxypropyl Cellulose-g-Poly(THF-co-epichlorohydrin)Graft Copolymer:Synthesis,Characterization and Properties

The novel quaternized hydroxypropyl cellulose-g-poly(THF-co-epichlorohydrin)graft copolymers,HPC-g-QCP(THF-co-ECH),have been successfully synthesized to combine the properties from hydrophilic hard HPC biomacromolecular backbone and hydrophobic flexible polyether branches.Firstly,the P(THF-co-ECH)living chains were synthesized by cationic ring-opening copolymerization of THF with ECH.Secondly,P(THF-co-ECH)living chains were grafted onto HPC backbone by reaction with-OH groups along HPC to produce HPC-g-P(THF-co-ECH)graft copolymers.Thirdly,the mentioned graft copolymers were quaternized by reaction with ternanyamine to generate functionalized HPC-g-QCP(THF-co-ECH).The HPC-g-QCP(THF-co-ECH)graft copolymers exhibited good antibacterial ability against S.aureus or E.coli bacteria.The ibuprofen(IBU)-loaded microparticles of HPC-g-(QC)P(THF-co-ECH)graft copolymers were prepared by electrospraying.The in vitro pH-responsive drug-release behavior of IBU reached up to 75%of drug-loaded at pH=7A.This quaternized graft copolymer was beneficial to solving the problems of a burst effect and fast release of HPC as drug carriers.

Synthesis of copolymers of 3-acryloyloxymethyl-3'-methyloxetane and 3-(2-(2-(2-Methoxyethylenoxy)ethylenoxy)ethylenoxy)-3'-methyloxetane and their ionic conductivity properties

An oxetane-derived monomer,3-acryloyloxy-methyl-3p-methyloxetane(AMO)was prepared from the reaction of 3-hydromethyl-3-methyloxetane with acryloyl chloride.The cationic ring-opening copolymerization of AMO with another oxetane-derived monomer,3-(2-(2-(2-methoxyethylenoxy)ethylenoxy)ethylenoxy)-3p-methyloxetane(MEMO)was conducted in CH2Cl2 solution using BF3·OEt2/1,4-butanediol as a co-initiator.The resulting copolymers were characterized by FTIR,1H NMR and Gel Permeation Chromatography(GPC)analyses,and it was found that the enchained ratio of AMO in the copolymers is far lower than its feed ratio.They were crosslinked in situ via the radical polymerization of the vinyl group initiated by BPO after doping with lithium trifluoromethanesulfonimide(LiTFSI)to give rise to tough polymeric electrolyte films.The ionic conductivity was measured at varying content of AMO and different concentration of lithium salt LiTFSI by AC impedance,and a maximum ion conductivity of 1.44×10^(−5) S/cm at 30℃ or 1.25×10^(−4) S/cm at 80℃ was attained in the sample PAM 33 at the mole ratio of O:Li=20.The DSC results indicated that Tg decreases with the increase of the proportion of AMO in the copolymer,well consistent with the ion conductivity trend.The TGA(thermo-gravimetric analysis)measurement revealed that this kind of copolymer electrolytes is more thermostable than their liquid counterparts.

Supramolecular hybrid hydrogels as rapidly on-demand dissoluble,self-healing,and biocompatible burn dressings

Despite decades of efforts,state-of-the-art synthetic burn dressings to treat partial-thickness burns are still far from ideal.Current dressings adhere to the wound and necessitate debridement.This work describes the first“supramolecular hybrid hydrogel(SHH)”burn dressing that is biocompatible,self-healable,and on-demand dissoluble for easy and trauma-free removal,prepared by a simple,fast,and scalable method.These SHHs leverage the interactions of a custom-designed cationic copolymer via host-guest chemistry with cucurbit[7]uril and electrostatic interactions with clay nanosheets coated with an anionic polymer to achieve enhanced mechanical properties and fast on-demand dissolution.The SHHs show high mechanical strength(>50 kPa),self-heal rapidly in~1 min,and dissolve quickly(4-6 min)using an amantadine hydrochloride(AH)solution that breaks the supramolecular interactions in the SHHs.Neither the SHHs nor the AH solution has any adverse effects on human dermal fibroblasts or epidermal keratinocytes in vitro.The SHHs also do not elicit any significant cytokine response in vitro.Furthermore,in vivo murine experiments show no immune or inflammatory cell infiltration in the subcutaneous tissue and no change in circulatory cytokines compared to sham controls.Thus,these SHHs present excellent burn dressing candidates to reduce the time of pain and time associated with dressing changes.