P-chloromethyl Styrene Research Articles

One-Step Synthesis of Self-Stratification Core-Shell Latex for Antimicrobial Coating

Herein, we describe a one-step method for synthesizing cationic acrylate-based core-shell latex (CACS latex), which is used to prepare architectural coatings with excellent antimicrobial properties. Firstly, a polymerizable water-soluble quaternary ammonium salt (QAS-BN) was synthesized using 2-(Dimethylamine) ethyl methacrylate (DMAEMA) and benzyl bromide by the Hoffman alkylation reaction. Then QAS-BN, butyl acrylate (BA), methyl methacrylate (MMA), and vinyltriethoxysilane (VTES) as reactants and 2,2'-azobis(2-methylpropionamidine) dihydrochloride (AIBA) as a water-soluble initiator were used to synthesize the CACS latex. The effect of the QAS-BN dosage on the properties of the emulsion and latex film was systematically investigated. The TGA results showed that using QAS-BN reduced the latex film's initial degradation temperature but improved its thermal stability. In the transmission electron microscopy (TEM) photographs, the self-stratification of latex particles with a high dosage of QAS-BN was observed, forming a core-shell structure of latex particles. The DSC, TGA, XPS, SEM, and performance tests confirmed the core-shell structure of the latex particles. The relationship between the formation of the core-shell structure and the content of QAS-BN was proved. The formation of the core-shell structure was due to the preferential reaction of water-soluble monomers in the aqueous phase, which led to the aggregation of hydrophilic groups, resulting in the formation of soft-core and hard-shell latex particles. However, the water resistance of the films formed by CACS latex was greatly reduced. We introduced a p-chloromethyl styrene and n-hexane diamine (p-CMS/EDA) crosslinking system, effectively improving the water resistance in this study. Finally, the antimicrobial coating was prepared with a CACS emulsion of 7 wt.% QAS-BN and 2 wt.% p-CMS/EDA. The antibacterial activity rates of this antimicrobial coating against E. coli and S. aureus were 99.99%. The antiviral activity rates against H3N2, HCoV-229E, and EV71 were 99.4%, 99.2%, and 97.9%, respectively. This study provides a novel idea for the morphological design of latex particles. A new architectural coating with broad-spectrum antimicrobial properties was obtained, which has important public health and safety applications.

Antifouling and antibacterial behavior of membranes containing quaternary ammonium and zwitterionic polymers

To overcome the organic-/bio- fouling of the membrane, a dual-functional ultrafiltration membrane containing quaternary ammonium and zwitterionic polymers via quaternization and surface radical polymerization was designed, and its antifouling and antibacterial behavior was studied. In this work, poly(vinylidene fluoride)/poly(methyl methacrylate-co-dimethylamino-2-ethyl methacrylate) (PVDF/P(MMA-co-DMAEMA)) blend membrane was quaternized by p-chloromethyl styrene (p-CMS), and the double bonds were introduced onto the membrane surface, which further participated in the polymerization of zwitterionic monomers on the membrane surface. The results indicated that the resultant membrane exhibited obviously improved hydrophilicity and weak positive charge (isoelectric point, 7.49). The membrane presented higher flux recovery ratio and lower protein adhesion compared with the pure PVDF membrane. Meanwhile, the membrane showed high-efficiency broad-spectrum antibacterial performance, that is, the bacteria killing efficiency of S. aureus and E. coli reached 98.2% and 97.0%, respectively. Moreover, the membrane effectively inhibited bacterial adhesion, which is important for the long-term antibacterial properties of membrane. This antifouling and antibacterial PVDF membrane may have potential in the long-term filtration process, especially when dealing with microbiologically contaminated water.

Tailored crystalline order of nascent polyethylene from metallocene supported on confined polystyrene

Building the desirable superstructure of polyethylene is one of the important topics for developing high value-added products, which brings potential benefits for society and sustainable development. Crystalline order is the ubiquitous superstructure for enhancing mechanical properties of polymeric materials. In this work, polystyrene copolymers (c-PS) are incorporated into pores of silica through the wet-impregnation procedure of styrene and p-chloromethyl styrene followed by the in-situ free-radical copolymerization. Metallocene catalyst is further immobilized on supported silica. This incorporated c-PS is proved to be coated on the surface of silica pore walls rather than blocking the interparticle channels. The swelling behavior of c-PS inside the pores are performed by pulsed field gradient NMR (PFG-NMR) and thermoporosimetry (TPM-DSC), where a swelling behavior is shown in the toluene owing to the matched solubility parameters between the c-PS and toluene. According to the swelling behavior of c-PS confined in the pores, a compartmentalization is created hindering the formation of chain overlaps and increasing the crystallinity order of nascent polymers. As a result, the nascent polyethylene with a high crystallinity (i.e., bulk crystallinity Xc,DSC = 72.9 % and linear crystallinity Xc,WAXD = 90.5 %) is synthesized. There is a considerable activity (i.e., 3.8 × 106 g PE·(molZr·h)−1) at 70 °C. Finally, the particle morphology of the nascent polyethylene is investigated based on the swelling behavior of c-PS.

Polymer-Assisted Biocatalysis: Effects of Macromolecular Architectures on the Stability and Catalytic Activity of Immobilized Enzymes toward Water-Soluble and Water-Insoluble Substrates.

The aim of this study is to develop efficient enzyme immobilization media that will enable the reuse of the biocatalysts over multiple cycles, increase their thermal stability, and attenuate their activity toward hydrophobic substrates for “green” transformations in aqueous media. For this purpose, amphiphilic AB and ABA block copolymers were synthesized and tested with laccase (a multicopper oxidase). In all cases, the hydrophilic B block consisted of poly(ethylene glycol), PEG, with molecular masses of 3, 5, 13, 20, or 13 kDa poly(ethylene oxide). The hydrophobic A blocks were made of linear poly(styrene), PS; hyperbranched poly(p-chloromethyl styrene); or dendritic poly(benzyl ether)s of generations 2, 3, and 4 (G2, G3, and G4) with molecular masses ranging from 1 to 24 kDa. A total of 23 different copolymers (self-assembling into micelles or physical networks) were evaluated. Notable activity enhancements were achieved with both micelles (up to 253%) and hydrogels (up to 408%). The highest enzymatic activity and thermal stability were observed with laccase immobilized in hydrogels consisting of the linear ABA block copolymer PS2.7k–PEG3k–PS2.7k (13 290 μkat/L, 65 °C, ABTS test). This represents a 1245% improvement over native laccase at the same conditions. At 25 °C, the same complex showed a 1236% higher activity than the enzyme. The highest polymerization yield for a water-insoluble monomer was achieved with laccase immobilized in hydrogels composed of linear–dendritic ABA copolymer G3–PEG5k–G3 (85.5%, 45 °C, tyrosine monomer). The broad substrate specificity and reusability of the immobilized laccase were also demonstrated by the successful discoloration of bromophenol blue, methyl orange, and rhodamine B over eight repetitive cycles.

Engineering of new methylstyrene farmin vinylic monomer and crosslinked poly(methylstyrene farmin) nanoparticles of narrow size distribution for antibacterial and antibiofilm applications

The vinylic monomer methylstyrene farmin (MSF) was synthesized by interacting p-chloromethyl styrene with farmin in basic distilled water. Crosslinked poly(methyl styrene farmin) nanoparticles (PMSF NPs) were then synthesized by dispersion co-polymerization of the MSF monomer with the crosslinking monomer tetra(ethylene glycol) diacrylate (TTEGDA) in an aqueous continuous phase. The effect of various polymerization parameters on the size and size distribution of the formed NPs has been elucidated. These PMSF NPs contain quaternary ammonium groups and long alkyl chain groups, and therefore are expected to possess efficient antibacterial and antibiofilm properties. The antibacterial and antibiofilm properties of PMSF NPs of 40 ± 9 nm and NPs-coated films were demonstrated. Due to their promising antibacterial and antibiofilm properties, these newly NPs could be utilized in a variety of industrial applications as a new type of biocide and antibiofilm additive.

Preparation and evaluation of hyperbranched p-chloromethyl styrene polymers/montmorillonite clay nanocomposites as dielectric materials

Hyperbranched polymers/montmorillonite clay modified with cetyl trimethyl ammonium bromide (MMT-CTAB) nanocomposites with polystyrene core were prepared by self-condensing vinyl polymerization via atom transfer radical polymerization of p-chloromethyl styrene monomer (CMS) alone or with styrene (St) and methyl methacrylate (MMA) monomers in the presence of MMT-CTAB acting as inimer with the double bond at one end and the alkyl-Cl unit at the other end. Three hyperbranched polymers/MMT-CTAB nanocomposites such as PCMS homopolymer/MMT-CTAB, PCMS-b-PSt copolymer/MMT-CTAB and PCMS-b-PSt-b-PMMA terpolymer/MMT-CTAB were prepared. The prepared hyperbranched polymers/MMT-CTAB nanocomposites were characterized via X-ray diffraction, dynamic mechanical thermal analyses and transmission electron microscopy for further applications as dielectric materials. Accordingly, several parameters were measured including dielectric permittivity (e′), A.C. conductivity (σ) and loss tangent (tan δ) in case of frequency and temperature ranging from 0.1 Hz to 100 kHz and 20–80 °C, respectively.

A novel cathode material based on polystyrene with pendant TEMPO moieties obtained via click reaction and its use in rechargeable batteries

In the present study, a new type of cathode-active polymeric material was synthesized via a synthetic strategy which involves a series of high-yield and simple chemical reactions performed on a commercially available and relatively cheap polymer, poly(p-chloromethylstyrene). Polymeric support for the electro-active TEMPO was obtained by nitroxide-mediated polymerization (NMP) of p-chloromethyl styrene. This polystyrene derivative was converted to a polymer with pendant electro-active TEMPO radical groups via an azidation reaction which was followed by a click reaction with an alkyne functionalized TEMPO derivative. The obtained polystyrene bearing TEMPO radical polymer possessed a high spin density of 1.4 × 1021 spin/g indicating that electro-active TEMPO groups were successfully attached to the polymer with high yield. The composite cathode material obtained by mixing this TEMPO functionalized polymer with graphite showed a reversible electrochemical redox behavior in a cyclic voltammetry (CV) study vs. Li metal anode. The Li-battery constructed using this cathode maintained 83 % of the its initial capacity (35 mAh/g) over 80 cycles with a cell potential of 3.8 V.

Facile synthesis of crosslinked core/shell silver nanoparticles with significantly improved thermal stability

A facile preparation of highly thermal stability silver nanoparticles (Ag NPs) protected by a crosslinked poly(p-chloromethyl styrene) (PCMS) shell and polystyrene (PS) brushes was reported in this work. Firstly, a triblock copolymer, PS-b-PCMS-b-PS, was synthesized by sequential reversible addition-fragmentation transfer (RAFT) polymerization of styrene and p-chloromethyl styrene using a trithiocarbonate chain transfer agent. Secondly, Ag NPs were obtained by in-situ reduction of silver nitrate using trithiocarbonate-containing PS-b-PCMS-b-PS as the stabilizer. Finally, ethylene diamine was used to quaternize and crosslink the PCMS inner-shell, leaving the outer-shell PS brushes preventing particle aggregation. Due to protection of the crosslinked PCMS inner-shell, Ag NPs were stable in solution for at least 18h while being heated at 110°C. Therefore, this method of combined in-situ reduction and inner-shell crosslinking is promising to scale-up the preparation of metal nanoparticles with good dispersibility and thermal stability, which has still remained challenging so far.

Graft copolymers via combination of cationic polymerization and atom transfer radical polymerization and their phase separation into spherical/worm-like nanostructures

Poly(p-chloromethyl styrene)-graft-poly(methyl methacrylate) (PCMS-g-PMMA) and poly(p-chloromethyl styrene)-graft-poly(benzyl methacrylate) (PCMS-g-PBzMA) graft copolymers with asymmetric branches are synthesized via the combination of cationic polymerization and atom transfer radical polymerization (ATRP). The process involves first, the preparation of poly(p-chloromethyl styrene) (PCMS-CH2Cl) macroinitiator without any cross-linking or side reactions through pendant benzyl chloride (−CH2Cl) functionality by cationic polymerization using a simple FeCl3-based initiating system at 25 °C. The as-synthesized PCMS-CH2Cl, without any transformation, is then used as the macroinitiator to graft PMMA and PBzMA branches by ATRP to produce PCMS-g-PMMA and PCMS-g-PBzMA graft copolymers of varying compositions with controlled molecular weight and moderately narrow polydispersities (M w/M n ≤ 1.32). The resulting PCMS21 -g-PMMA232 graft copolymer in thin film form phase separates into spherical morphology with an average diameter of 170 ± 72 nm. Whereas the PCMS21 -g-PBzMA156 graft copolymer gives worm-like nanostructures with an average length of 94 nm and width of 31 nm due to phase separation as visualized through atomic force microscopy. On the other hand, the phase-separated morphology is not very well-defined for other graft copolymers (PCMS113 -g-PMMA227 and PCMS113 -g-PBzMA154) thin films containing longer PCMS chains. This approach represents a rapid and convenient route to prepare unique spherical/worm-like polymer nanostructures.

Synthesis and characterization of novel poly (p-methyl styrene) containing azetidine moieties and their optical and semiconducting properties

The p-methyl styrene-based monomer, p-methoxy-3-(1-cyclohexyl) azetidinyl styrene (PMAS) was synthesized by reacting N-cyclohexylazetidinol with p-chloromethyl styrene in tetrahydrofurane solvent at room temperature in the presence of potassium tert-butoxide (t-BuOK). The free-radical initiated polymerization of PMAS was carried out in 1,4-dioxane solution at 70±1°C using 2,2′-azobisisobutyronitrile (AIBN) as an initiator. The synthesized monomer and homopolymer have been characterized fully by a range of spectroscopic, thermal analysis and SEM analysis techniques. This homopolymer has been converted into a novel salts by reaction with the iodomethane(CH3I) at different times (60, 180, 300min). The electrical conductivity of the poly(PMAS) salts was measured and the poly(PMAS) salts exhibit the semiconducting behavior. The optical band gap and electrical resistance values of this polymers were obtained to be 3.79, 3.77, 3.82eV, and 6.63×108, 7.09×109, 2.28×1010Ω, respectively.

Self-assembly of amphiphilic random co-poly(ionic liquid)s: the effect of anions, molecular weight, and molecular weight distribution

Self-assembly behavior of amphiphilic random co-poly(ionic liquid)s in aqueous solution was investigated in this work. An imidazolium-type homopolymer, poly(1-(4-vinylbenzyl)-3-methyl imidazolium chloride) (denoted as PIL-[Cl]), was synthesized via reversible addition fragmentation chain transfer (RAFT) polymerization of p-chloromethyl styrene, and followed by post-polymerization with methylimidazole (or vinylimidazole). Partial anion-exchange of PIL-[Cl] with PF6− anions yielded amphiphilic random copolymers, PIL-[Cl]x[PF6]y (suffixes x, y represent the relative molar ratio of Cl− and PF6− anions). Self-assembly morphologies of PIL-[Cl]x[PF6]y in aqueous solution as a function of copolymer composition (anions), molecular weight, and molecular weight distribution were investigated. The size of well-defined PIL-[Cl]x[PF6]y spherical micelles increased dramatically with increasing molecular weight distribution, while the anions and molecular weight show little effect on the micelle size. Furthermore, self-assembly of amphiphilic random ionic copolymers with the vinylimidazole groups yielded colloidosomes, which might be due to the polymerization of vinylimidazole groups.

Enhanced Dielectric Response in Polyurethane Based All-Organic Nanocomposite

A high dielectric constant nano-composite was fabricated using polyurethane (PU) as matrix and poly (p-chloromethyl styrene) (PCMS) grafted with copper phthalocyanine oligomer (CuPc, a planar multiring semiconductor with dielectric constant>105) (name the grafting product as PCMS-g-CuPc) as filler. According to the TEM-observed morphologies, PCMS-g-CuPc balls (~80 nm) distribute uniformly in PU matrix, while in PCMS-g-CuPc balls the PCMS acts as “matrix” which contains dispersed CuPc particles with a average size of ca. 25nm [1/20 of that of CuPc in simple blend of PU and CuPc (PU/CuPc)]. At 100Hz, the dielectric constant of the nanocomposite reaches 345, almost 7 times higher than that of PU/CuPc. The enhanced dielectric response in the nano-composite can be explained by the remarkably strengthened interface exchange coupling effect as well as the Maxwell-Wagner-Sillars polarization mechanism due to the significantly reduced CuPc particle size in the nano-composite.

Synthesis and Thermal Property of Linear Chloromethylated Polystyrene

Polystyrene (PS) was synthesized by emulsion polymerization. 1,4-bis(chloromethoxy)butane (BCMB) was synthesized using 1,4-butanediol, formaldehyde and phosphorus trichloride as raw material. The linear poly(p-chloromethyl styrene) (PS-Meyl-Cl) was prepared high effectively using BCMB and anhydrous aluminium trichloride as the chloromethylation reagent and catalyst, respectively. In this method, carcinogenic compound (chloromethyl ether etc.) was avoided. The resultant polymers were characterized by gel permeation chromatography (GPC), Fourier transform infrared spectrometer (FTIR) and thermogravimetric analyzer. The results show that the molecular weight (Mw) of PS is big. BCMB has been prepared because of the strong absorption band observed at 1130cm-1 (due to C-O-C bond stretching vibration) and two new bands at 640 and 1315cm-1 (due to the bending vibration of C-Cl bond and stretching vibration of C-H bond in -CH2Cl, respectively). Chloromethyl groups were introduced into benzene ring of PS because of the appearance of the absorption peaks at 676 and 1419cm-1 (due to the bending vibration of C-Cl bond and stretching vibration of C-H bond in -CH2Cl, respectively) in the FTIR spectra. The thermal stability of PS-Meyl-Cl was decreased with increasing chloromethyl group. Moreover, there are two decomposing stages. The reaction condition is gentle and the operation is safe, simple and economical.

ELIMINATION OF GELATINIZATION USING MIXTURE OF SOLVENTS IN THE ATRP REACTION TO SYNTHESIZE MULTI ARM STAR POLYMERS

Hyperbranched polystyrene synthesized by the copolymerization of styrene and p-chloromethyl styrene was used as initiator to initiate the ATRP reactions of styrene and methyl methacrylate with CuCl / pentamethyldiethylenetriamine as catalysts.The reaction dynamics were studied.It was found that the ATRP the reaction gelatinized easily in good solvent chlorobenzene.The monomer conversions before gelation were small.If poor solvent 1,4-dioxane was added in chlorobenzene before gelation,the gelatinization reactions could be eliminated efficiently.The monomer conversions could reach to high values and muti-arm star polymers with high molecular weight about a million were synthesized.This is new method to prepare multi-arm star polymers with high molecular weight.

Synthesis and Characterization of Composites from Layered Silicates and Homo- and Copolymers of 2-Hydroxyethyl Methacrylate and P-Chloromethyl Styrene Obtained by In Situ Radical (Co)polymerization

The hybrids 2-hydroxyethyl methacrylate – chlorometylstyrene – modified montmorillonite were synthesized by means of “in-situ” radical (co)polymerization. The composites were analysed by thermal analysis (DSC-TGA-MS), Fourier-Transform Infrared Spectroscopy (FT-IR), nuclear magnetic resonance (1H-NMR), X-ray diffraction, and scanning electron microscopy (SEM). The influence of the polymerization conditions and compositions on the thermal stability and morphology of the obtained composites is discussed.

Novel Preparation of Polymer-Supported Iodobenzene and Its Synthetic Utility as a Recyclable Reagent with m-Chloroperbenzoic Acid

Three novel polymer-supported iodobenzene compounds A o , A 6 , and A 10 were prepared from the reaction of commercially available cross-linked poly(p-chloromethyl)styrene with m-iodobenzylalcohol, 6-(m-iodobenzyloxy)-I-hexanol, and 10-(m-io-dobenzyloxy)-l-decanol. Their catalytic reactivity and reusability for the oxidative α-tosyloxylation of ketones and the cyclization of N-methoxy-2-arylethanesulfonamides in the presence of m-chloroperbenzoic acid (mCPBA) were confirmed to provide α-tosyloxyketones and N-methoxy-3,4-dihydro-2,1-benzothiazine-2,2-dioxides, respectively, in good yields.

Preparation of Crosslinked Polymeric Nanocapsules by Surface-Initiated Self-Condensing Vinyl Polymerization on Silica Templates

We developed a process to fabricate crosslinked polymeric nanocapsules with about 10-40 nm hollow cores. These crosslinked polymeric nanocapsules were fabricated via the surface-initiated self-condensing vinyl polymerization (SI-SCVP) of p-chloromethyl styrene (CMS) from initiator modified silica nanoparticles with atom transfer radical polymerization (ATRP) technique. The silica templates were removed by HF etching to produce the crosslinked polymeric nanocapsules after the grafted hyperbranched polymers had been crosslinked. Transmission electron microscopy (TEM) was used to characterize the products and to demonstrate that the polymeric nanospheres were hollow. FTIR spectroscopy showed that the silica templates were completely removed by etching.

A large enhancement in dielectric properties of poly(vinylidene fluoride) based all-organic nanocomposite

A nanocomposite was fabricated using poly(vinylidene fluoride) (PVDF) as matrix and poly(p-chloromethyl styrene) (PCMS) grafted with high dielectric constant copper phthalocyanine oligomer (CuPc) (PCMS-g-CuPc) as filler. Transmission electron microscopic morphologies reveal that the PCMS-g-CuPc particle size of ca. 80nm in average are dispersed in PVDF matrix, while in PCMS-g-CuPc particles the PCMS acts as “matrix” which contains dispersed CuPc balls with a average size of ca. 25nm [1/20 of that of CuPc in simple blend of PVDF and CuPc (PVDF/CuPc)]. The nanocomposite with only 15wt% CuPc can realize a dielectric constant of 325 at 100Hz, about 7 times larger than that of PVDF/CuPc, and nearly 40-fold enhancement with respect to that of the pure PVDF. The significant enhancement of dielectric response can be attributed to the remarkably strengthened exchange coupling effect as well as the Maxwell–Wagner–Sillars polarization mechanism.

PVDF based all-organic composite with high dielectric constant

High dielectric constant copper phthalocyanine oligomer (o-CuPc) was chemically grafted to poly(p-chloromethyl styrene) (PCMS) to improve its dispersibility in PVDF. From SEM results, the size of o-CuPc-g-PCMS particles in the blend of poly(vinylidene fluoride) (PVDF) and o-CuPc-g-PCMS (o-CuPc-g-PCMS/PVDF) was about 70nm, less than 1/7 the size of o-CuPc in o-CuPc/PVDF. In addition, o-CuPc-g-PCMS in o-CuPc-g-PCMS/PVDF showed much improved dispersibility. Both of the improvements obviously enhanced the electric properties of the composite. The dielectric constant of o-CuPc-g-PCMS/PVDF was more than 325 (100Hz), which was about 7 times higher than that of o-CuPc/PVDF. The dielectric constant at high frequencies (∼1MHz) was also high (∼130).

Well-Defined Dendritic-Graft Copolymer Grafted Silica Nanoparticle by Consecutive Surface-Initiated Atom Transfer Radical Polymerizations

To obtain well-defined dendritic-graft copolymer grafted silica nanoparticles (SN-HBP-PMMA), the surface halogen atom of the hyperbranched polymer grafted silica nanoparticles (SN-HBP), by surface-initiated self-condensing vinyl polymerization (SI-SCVP) of p-chloromethyl styrene (CMS) from functionalized silica nanoparticles, was used as initiator for the surface-initiated atom transfer radical polymerization (SI-ATRP) of methyl methacrylate (MMA) for the first time. The well-defined hyperbranched polymer and the dendritic-graft copolymer grafted were validated by 1H NMR analysis. And, the dispersibility of the well-defined polymer grafted silica nanoparticles was investigated with a transmission electron microscope (TEM).