Biocidal polymers: Synthesis,antimicrobial activity,and possible toxicity of poly (hydroxystyrene‐co‐methylmethacrylate) derivatives

Functionalized polymers have gained much interest in the last decades. This is due to their functional group and their polymer nature that give them unique properties and more advantages than the corresponding small molecules. In this trend, polyhydroxystyrene‐co‐MMA was modified to introduce amino group in the side chain of the polymer. The amine modified polymer was reacted with two classes of active compounds. The first class is aldehydes such as vanilline, p‐hydroxybenzaldehyde, p‐chlorobenzaldehyde, and anisaldehyde. The second class is phenolic esters such as p‐hydroxymethylbenzoate, 2,4‐dihydroxymethyl benzoate, and methyl salicylate. The antimicrobial activities of the polymer and modified polymer with these two classes were explored with Gram‐negative bacteria (Escherichia coli), Gram‐positive bacteria (Bacillus subtilus), fugus like yeast (Candida albicans SC5314), and pathogenic molds (Aspergillus flavus, Trycophyton rubrum, and F. oxysporium). In vitro studies indicated that the start polymer did not affect on the test microorganisms, in contrary to its derivatives. The diameter of inhibition zone varied according to the active group in the modified polymer, polymer microstructure, and the test microorganism. Derivatives I, II, and III were selected among the most effective antimicrobial compounds. Their inhibitory effects on the ratio of surviving cell number (M/C) increased by increasing derivatives concentrations. Derivatives I and II were inhibitorier to C. albicans and molds than to bacteria while derivative III was only antibacterial. These derivatives seemed toxic to Brine shrimp by increasing their concentrations above 10 ppm, with derivative III being the less toxic, compared to others. To clarify this toxic effect and to decrease the toxicity of these derivatives, more detailed studies are necessary, and this will be focused in the nearest future. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Synthesis and characterization of poly(pyridylurea) and poly(pyridylthiourea), potentially semiconducting polymers

Poly(pyridylureas) and poly(pyridylthioureas) were synthesized by reacting 2,6‐diaminopyridine with phosgene and thiophosgene, respectively, using THF and pyridine as solvent. The synthesized polymers were characterized by IR‐spectroscopy, elemental analysis, and X‐ray photoelectron spectroscopy. Thermal stability of the polymers was determined by thermal degradation between 35°C and 700°C. The 50% weight loss of polypyridylureas was above 400°C while for the polypyridylthioureas it was above 450°C. Undoped poly(pyridylureas) and poly(pyridylthioureas) behave as semiconductors, σ = 10^?9 (Ω cm)^?1. After doping with I₂ and SbF₅, the electrical conductivity increases several orders of magnitude, σ = 10^?7(Ω cm)^?1. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007     

Synthesis of succinylated poly(4‐hydroxystyrene) and its application for negative‐tone photoresist

Atom transfer radical polymerization (ATRP) was used to prepare poly(acetoxystyrene) (PAS) with a controlled molecular weight and narrow polydispersity. Using 1‐phenylethylbromide (PEBr)/CuBr/Cu(0)/2,2′‐bipyridine as an initiating system, the heterogeneous ATRP of 4‐acetoxystyrene was carried out to form PAS as a precursor polymer. The reaction follows the first‐order kinetics with respect to the conversion of monomer. A linear molecular weight (polydispersities Mw/Mn = 1.07–1.27) indicates the “living”/controlled nature of polymerization. The obtained PAS was chemically modified to obtain succinylated poly(hydroxystyrene) (Succ‐PHS). The formulation of Succ‐PHS, crosslinker (benzoguanamine‐formaldehyde), and triphenylsulfonium triflate (TPST) as a photo acid generator (PAG) was carried out by UV irradiation using an i‐line tool. The performance of the resultant polymer as the negative resist pattern photoresist for photolithography was studied with instrumental techniques. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 3560–3566, 2007     

Miscibility of polymer blends of poly(styrene‐co‐4‐hydroxystyrene) with bisphenol‐A polycarbonate

The miscibility of blends of bisphenol‐A polycarbonate (BAPC) and tetramethyl bisphenol‐A polycarbonate (TMPC) with copolymers of poly(styrene‐co‐4‐hydroxystyrene) (PSHS) was studied in this work. It has been demonstrated that BAPC is miscible with PSHS over a region of approximately 45–75 mol % hydroxyl groups in the copolymer. TMPC has a wider miscible window than BAPC when blended with PSHS. The blend miscibility was considered to be driven by the intermolecular attractive interactions between the hydroxyl groups of the PSHS and the π electrons of the aromatic rings of both polycarbonates (PCs). As the FTIR measurements showed, after blending of BAPC with PSHS, there is no visible shift of the carbonyl band of BAPC at 1774 cm⁻¹, whereas the stretching frequency of the free hydroxyl groups of the copoly‐ mers at 3523 cm⁻¹ disappeared. The large positive values of the segment interaction energy density parameter B_st‐HS calculated from the group contribution approach indicated that the intramolecular repulsive interaction may also have played a role in the promotion of the blend miscibility. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 74: 639–646, 1999     

Influence of branching on the properties of poly(ethylene terephthalate) fibers

A series of branched poly(ethylene terephthalate) samples was prepared by employing 0.07–0.42 mol % trimethylolpropane (TMP) for melt polycondensation. These polymers were characterized with respect to molar mass, intrinsic viscosity, and melt viscosity. Spinning into fibers took place at spinning speeds ranging from 2500 to 4500 m/min. The molecular orientation of the fibers as measured by birefringence and polarized fluorescence decreases with growing amounts of TMP, as does crystallinity. Thus with slightly branched polymers, higher spinning speeds than with a linear polymer can be used to achieve a certain property profile. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 74: 728–734, 1999     

Synthesis and thermal properties of randomly branched poly(butylene isophthalate) containing sodium sulfonate groups

Randomly branched poly(butylene isophthalate) samples containing sodium sulfonate groups were prepared from dimethyl isophthalate, 3,5‐bis(carbomethoxycarbonyl) benzene sulfonate, tris(hydroxyethyl) isocyanurate, and 1,4‐butanediol, according to the well‐known two‐stage polycondensation procedure. The polymers, containing various amounts of branching units and ionic groups, demonstrated to be soluble in the most common organic solvents, an evidence that gelation was not reached under the polymerization conditions adopted. The thermal behavior was examined by thermogravimetric analysis and differential scanning calorimetry. The sulfonate as well as the branching units had only a limited effect on the thermal stability, which slightly decreased with respect to pure poly(butylene isophthalate). The analysis carried out using DSC technique showed that the T_m of the copolymers decreased with increasing counit content, differently from T_g, which, on the contrary, increased. Baur's equation was found to describe well the T_m‐composition data. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 1374–1379, 2006     

Properties of branched and network poly(vinyl alcohols) prepared with poly(vinyl alcohol) having aldehyde groups at the chain ends

Branched and network poly(vinyl alcohols) (PVAs) were prepared with inter-acetalization of the PVA with aldehyde groups at the chain ends which was prepared by the cleavage of 1,2 glycol bonds in commercial PVA. The numbers of branches estimated from molecular weights were compared with those estimated by theory. Huggins' constant and crystallinity decreased with increasing branch number. Dissolution of branched PVAs into dimethylsulphoxide was not so easy compared with commercial PVA. The colour of branched PVA–iodine complex decreased rapidly with standing while that of commercial PVA decreased gradually. Network PVAs with Young's modulus of 1–8 MPa were prepared.     

Phase separation phenomena in aqueous solutions of amphiphilic poly(ethylene oxide) star polymers

Three- and four-armed star polymers with poly(ethylene oxide) arms capped with hydrophobic end-groups were synthesized from nonylphenoxypoly(ethylene glycol)s and well defined tri- and tetraisocyanates. The latter were hydrosilylation products of m-isopropenyl-,-dimethylbenzyl isocyanate (m-TMI). In aqueous solution the arm ends associate, and above a critical star concentration the mixture phase separates into a dilute phase and a condensed gel phase. Their respective polymer concentrations remain constant as long as the two phases coexist, their volume fractions being proportional to the total polymer concentration. Brookfield viscosity measurements confirm the formation of the gel phase which resembles an amphiphilic hydrogel. It exhibits a high affinity for hydrophobic compounds.     

Studies with gradient polymers of polystyrene and poly(methyl acrylate)

A series of [net-polystyrene]-ipn-[net-poly(methyl acrylate)] systems with gradients of poly(methyl acrylate) in a polystyrene matrix are prepared and tested mechanically. The results showed no distinct differences from that of corresponding interpenetrating polymer network (IPN) samples with similar compositions, in contrast to the substantially improved fracture strains obtained for [net-poly(methyl methacrylate)]-ipn-[-net poly(methyl acrylate)] gradient systems and their nongradient IPN's in our previous work. Hence, it is concluded that the toughening effect of gradient structure observed is not universally applicable for all gradient systems but it is unique for the acrylic system studied. Moduli-temperature responses and dynamic mechanical spectra of gradients and IPN's prepared in the current study are also presented. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 73: 1721–1725, 1999     

Synthesis and gas transport properties of novel poly(aryl ether ketone)s with branched structure

Poly(aryl ether ketone)s (PAEKs) based on 2‐(3′‐trifluoromethylphenyl) hydroquinone and 4,4′‐difluorobenzophenone were synthesized and characterized in the presence or absence of 2,4′,6‐trifluorobenzophenone (BB′₂ monomer). The influence of the incorporation of a branched structure (BB′₂ monomer) on the gas transport properties of PAEKs was investigated. The results showed that PAEKs with a branched structure possess a higher permeability and selectivity than PAEKs without a branched structure. Moreover, improvements in the permeability and selectivity were enhanced with increasing content of BB′₂ monomer. This synergistic effect on permeability and selectivity was mainly due to the higher fractional free volume and the unique size and distribution of free volume holes arising from the incorporation of the branched structure. © 2013 Society of Chemical Industry     

A comparative study of the structure-property behavior of highly branched segmented poly(urethane urea) copolymers and their linear analogs

The solid-state structure-property behavior of highly branched segmented poly(urethane urea) (PUU) copolymers and their linear analog was investigated. A limited study of their solution rheological behavior was also undertaken. The linear PUUs were synthesized by the two-step prepolymer method, whereas the oligomeric A₂+B₃ methodology was utilized to synthesize the highly branched materials. The soft segments (SS) were either poly(tetramethylene oxide) (PTMO) or poly(propylene oxide) (PPO). All copolymers utilized in this study, with one exception, contained 28 wt% hard segment (HS) content. DMA, SAXS, and AFM studies indicated that the linear as well as the highly branched PUUs were microphase separated. The SS T_g of the highly branched PUUs was nearly identical to that of their respective linear analogs. However, the linear copolymers exhibited broader and less temperature sensitive rubbery plateaus, both attributed to one or both of two reasons. The first is better hydrogen bonding organization of the HS phase as well as greater HS lengths than in the highly branched analogs. The second parameter is that of a potentially higher chain entanglement for the linear systems relative to the branched analogs. Tapping-mode AFM phase images confirmed the microphase morphology indicated by SAXS and DMA. Ambient temperature strain-induced crystallization was observed in the PUU based on PTMO 2040 g/mol at a uniaxial strain of ca. 400%, irrespective of the chain architecture. Stress-strain, stress relaxation, and mechanical hysteresis of the highly branched copolymers were in general slightly poorer than that of their linear analogs. Ambient temperature solution viscosity of the highly branched materials in dimethyl formamide was substantially lower that that of the linear samples of nearly equal molecular weight.     

Synthesis of a branched poly(phenylene ethylene) with bromomethyl groups as an organosoluble and functional parylene

We synthesized a branched poly(phenylene ethylene) (BPPE) with bromomethyl groups from 1,3,5‐tris(bromomethyl)benzene derivatives via the Wurtz coupling reaction. In the case of 1,3,5‐tris(bromomethyl)‐2,4,6‐trimethoxybenzene as a monomer, the obtained polymer (M_n = 6100, M_w/M_n = 1.9) had bromomethyl groups. The ¹HNMR analysis showed that a very large number of unreacted bromomethyl groups (Ph‐CH₂Br) remained in the BPPE; the reaction of this polymer with phenolic hydroxyl groups proceeded quantitatively. This suggested that BPPEs can be functionalized using unreacted bromomethyl groups, making them a very attractive starting point for the creation of functionalized BPPEs with further enhanced processability. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

Studies on aluminum-isopropoxide doped poly(ethylene oxide), poly(vinyl alcohol), and poly(ethylene oxide)-poly(vinyl alcohol) blends

Poly(ethylene oxide), poly(vinyl alcohol), and their blend in a 40 : 60 mole ratio were doped with aluminum isopropoxide. Their structural, thermal, and electrical properties were studied. Aluminum isopropoxide acts as a Lewis acid and thus significantly influences the electrical properties of the polymers and the blend. It also acts as a scavanger for the trace quantities of water present in them, thereby reducing the magnitude of proton transport. It also affects the structure of polymers that manifests in the thermal transformation and decomposition characteristics. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 69: 2147–2157, 1998     

Synthesis and characterizations of branched poly(butylene succinate) copolymers with 1,2‐octanediol segments

Branched poly(butylene succinate) (PBS) copolymers were synthesized, from succinic acid (SA), 1,4‐butanediol (1,4‐BD), and 1,2‐octanediol (1,2‐OD) through a two‐step process containing esterification and polycondensation, with different mole fractions of 1,2‐OD segments. The branched PBS copolymers were characterized with ¹H‐NMR, differential scanning calorimetry (DSC), wide angle X‐ray diffraction (WAXD), thermogravimetric analysis (TGA), dynamic rheological testing, and tensile properties analysis. The results of DSC and WAXD show that, with the increasing of the 1,2‐OD segments content, the glass transition temperature (T_g), melting temperature (T_m), crystallization temperature (T_c), and the degree of crystallinity (X_c) decrease. While the crystal structure of PBS does not change by introducing 1,2‐OD segments. The results of TGA and dynamic rheological testing indicate that the thermal stability of neat PBS is improved with the addition of 1,2‐OD segments. The incorporation of 1,2‐OD segments has some effects on the rheological properties of PBS, such as complex viscosities (|η*|), storage modulus (G′), and loss modulus (G″). Tensile testing demonstrates that the elongation at break is improved significantly with increasing 1,2‐OD segments content, but without a notable decrease of tensile strength. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

One-step fabrication of branched poly(vinyl alcohol) nanofibers by magnetic coaxial electrospinning

Branching has been emerging in 3-D interconnecting building blocks. Branched and hyperbranched poly(vinyl alcohol) (PVA) nanofibers were fabricated by coaxially electrospinning two-liquids under an alternating magnetic field in a facile manner. Both the PVA nanofiber trunks with diameter of 100–200 nm and the PVA nanofiber branches with diameter of 10–30 nm were formed in a single step. The length and the morphology of the branched PVA nanofibers could be controlled through a rational design of the magnetic field. The facile technique may readily be extended to prepare 3-D branched nanofibers from other materials such as various polymers and polymer–ceramic materials. Moreover, the multifunctional and multicomponent materials with branched nanostructure could be expected by using the magnetic coaxial electrospinning technique. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

Crystallization study on absorbable poly(p‐dioxanone) polymers by differential scanning calorimetry

An investigation was carried out on the crystallization behavior of p‐dioxanone polymers using differential scanning calorimetry (DSC). Kinetic analyses were performed on data collected primarily during isothermal crystallization. Isothermal data were treated within the framework of the classical Avrami equation. Using this approach, both the Avrami exponent, n, and the crystallization half‐time, t_1/2, were evaluated and their implications are discussed for each system studied. It is shown that a small change in the polymer's composition greatly affects the crystallization kinetics, as well as the crystallizability of the materials. Additionally, nonisothermal crystallization under controlled heating and cooling rates was explored. In the case of cooling from the melt, the Ozawa theory and the recently proposed Calculus method were employed to describe the nonisothermal crystallization kinetics. In view of our results, the validity of these two estimation techniques for determining important kinetic and morphological parameters is also discussed. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 79: 742–759, 2001     

Synthesis and characterization of coordination polymers of Hg(II) with poly(thiooxamides)

Coordination polymers of Hg(II) with dithiooxamide, poly(ethylene thiooxamide), poly(butane thiooxamide), and poly(hexane thiooxamide) have been synthesized. All coordination polymers are solid compounds insoluble in common organic solvents. Coordination polymers have been characterized by elemental analysis, IR spectra, and thermogravimetric analysis and structures have been proposed leading to coordination of metal through S alone as well as N and S both. Thermal stability of the polymers has also been discussed.     

The complicated influence of branching on crystallization behavior of poly(ethylene terephthalate)

The randomly branched poly(ethylene terephthalate) (BPET) was prepared by bulk polycondensation from dimethyl terephthalate (DMT) and ethylene glycol (EG), with 0.4–5.0 mol % (with respect to DMT) of glycerol (GL) as a branching agent. The glass transition and crystallization behavior was studied by differential scanning calorimetry (DSC). It was found that the glass transition temperature of BPET reduced with the increasing content of GL until 1.2 mol %, and then increases a little at high degrees of branching. When compared with a linear PET, the crystallization temperature of BPET from the melt shifted to higher temperature as GL content was smaller than 1.2 mol %, and then became lower while GL load was added. Nonisothermal crystallization kinetics was studied through the modified Avrami analysis. It was revealed that the overall crystallization rate parameter of BPET became larger when the GL content was less than 1.2 mol %, then turned to lower at higher branching degree. This indicated that low degree of branching could enhance the overall crystallization of poly(ethylene terephthalate) (PET), whereas high degree of branching in the range of 3.5–5.0 mol % would block the development of crystallization. On the basis of Hoffman's secondary crystallization theory, the product σσ_e of the free energy of formation per unit area of the lateral and folding surface was calculated. According to the change of the product σσ_e with the degree of branching, a possible explanation was presented to illuminate this diverse effect of different degrees of branching on crystallization. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

聚二甲基二烯丙基氯化铵杀生性能与机理研究进展

该文对聚二甲基二烯丙基氯化铵(PDMDAAC)的杀生性能与机理研究进行了综述。针对目前国内外关于PDMDAAC杀生性能与机理的研究现状,尝试从应用领域、作用对象、作用方式和作用效果等方面,对PDMDAAC的杀生性能研究进行了归纳,并简述了PDMDAAC杀生机理研究的进展。在此基础上,指出现有研究对PDMDAAC的杀生性能认识不足,尚未真正涉及PDMDAAC的杀生机理。最后,对今后PDMDAAC杀生性能与机理研究工作提出了若干建议。     

Synthesis and chemical modification of new luminescent substituted poly(p-phenylene) polymers

A new acyl-functionalized poly(p-phenylene) (Ac-PPP) was synthesized by Yamamoto cross-coupling and chemically modified to obtain an anthracene-containing derivative (An-PPP). The chemical structures of the polymers were confirmed by ¹H-NMR, ¹³C-NMR, and FTIR spectroscopic analysis. They are fully soluble in common organic solvents and have number-average molecular weight of 2.70 × 10³ and 5.26 × 10³ g mol⁻¹ for Ac-PPP and An-PPP, respectively. The optical properties of the polymers were investigated by UV–visible absorption and photoluminescence spectroscopies. A green emission was observed in Ac-PPP solid thin film and a yellow one in the anthracene-containing polymer An-PPP. The optical bandgap values were 3.21 and 3.08 eV for Ac-PPP and An-PPP, respectively. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012