Surface‐grafting of ground rubber tire by poly acrylic acid via self‐initiated free radical polymerization and composites with epoxy thereof

Commercially available recycled ground rubber tire (GRT) particles, found to contain persistent mechano‐free radicals confirmed by electron paramagnetic spectroscopy for the first time self‐initiates free radical polymerization of acrylic acid (AA). The poly acrylic acid (PAA) grafted GRT (PAA‐g‐GRT) was confirmed by Attenuated Total Reflection Fourier Transform Infrared spectroscopy, X‐ray photoelectron spectroscopy, and thermogravimetric analysis (TGA). Epoxy composites using the PAA‐g‐GRT as filler were prepared and their mechanical properties were studied. The PAA‐g‐GRT/epoxy composite showed higher mechanical properties with an increase of modulus up to 180% as compared with the neat GRT/epoxy composite. Surface morphology of GRT, neat GRT/epoxy, and PAA‐g‐GRT/epoxy composites were analyzed by scanning electron microscopy. This technology introduces a new concept to functional and reactive recycling and the cost effective utilization of renewable resource green materials. POLYM. COMPOS., 2013. © 2013 Society of Plastics Engineers     

Polymer/metal interpenetrating phase composites prepared via γ‐ray initiated in‐situ emulsion polymerization

The poly(methylmethacrylate)/metal and poly(butylacrylate‐co‐styrene)/metal interpenetrating phase composites (IPCs) were prepared via γ‐ray irradiation in‐situ bulk and emulsion polymerization, respectively. The monomers were first introduced into open‐cell aluminum foam and aluminum alloy foam and were in‐situ polymerized by γ‐ray irradiation at room temperature. The characterization and compressive test results showed that this method expands the variety of the polymer component resulting in a useful range of physical properties of the IPCs, such as density and porosity. The PMMA/metal IPC has a high polymer filling ratio, modulus and exhibits a similar compressive behavior to that of PMMA. On the other hand, the P(BA‐co‐St)/metal IPC has a relatively low polymer filling ratio and its compressive behavior is similar to that of metal foam matrix, but it has wider plastic plateau than the component metal foams, like the case of metal foam filled with rubber. POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers     

Preparation and characterization of coaxial mullite/polypyrrole fibrous nanocomposites via self‐assembling and in situ surface‐initiated polymerization

After mullite fibers particles (MFPs) were surface modified, conductive polypyrrole (PPy) layer was chemically grafted on the surface of the self‐assembled monolayer (SAM) coated MFPs, via in situ surface‐initiated polymerization, resulting in SAM‐MFPs/PPy composites. The composites possess high electrical conductivity at room temperature, weakly temperature dependence of the conductivity. The nanocomposite electrochemical properties displayed nearly symmetric charge–discharge characteristics and an ideal rectangular cyclic voltammogram. X‐ray diffraction analysis confirmed that the main peaks of SAM‐MFPs/PPy composites are similar to the SAM‐MFPs, which reveal that the crystal structure of SAM‐MFPs is well‐maintained after the coating process under polymerization reaction conditions and exhibit semicrystalline behavior. Thermogravimetric analysis shows that the thermal stability of SAM‐MFPs/PPy composites was enhanced and these can be attributed to the retardation effect of amine functionalized MFPs as barriers for the degradation of PPy. The morphology of SAM‐MFPs/PPy composites showed the coaxial fibrous structure. POLYM. COMPOS., 35:892–899, 2014. © 2013 Society of Plastics Engineers     

Preparation magnetite core/coated with polystyrene shell hybrid materials via redox interfacial‐initiated emulsion polymerization

In this article, we describe a novel redox interfacial‐initiated micro‐emulsion polymerization (RIEP) to prepare hollow polystyrene microspheres with magnetite nanoparticles (MPs) core and polystyrene (PS) shell (MPs‐PS) under ambient pressure. The emulsion was constituted water‐based magnetic ferro‐fluid as dispersing phase and organic solvent and styrene (St) as continuous phase. Cumene hydroperoxide (CHPO)/iron (II) sulfates (FS) as the redox initiation system, the water‐soluble FS acted as the reducing component and the oil‐soluble CHPO as the oxidant component of the redox initiation system. Therefore, the primary radicals are produced mainly at the oil/water interface to initiate the polymerization of styrene to form polymer shell. The final products thoroughly characterized by X‐ray powder diffraction, Fourier transform infrared spectroscopy, transmission electron microscopy, field‐emission scanning electron microscopy, thermogravimetric analysis, dynamic light scattering, and X‐ray photoelectron spectroscopy, which showed the formation of hollow magnetite/polystyrene nanocomposite microspheres. Magnetic measurements were carried out at room temperature using a vibrating sample magnetometer. The saturation magnetization (M_s), remanent magnetization (M_r) and coercivity (H_c) is 30 emu/g, 15 emu/g and 370 Oe, respectively. The results revealed that the hybrid materials microspheres were super‐paramagnetic. POLYM. COMPOS., 31:1846–1852, 2010. © 2010 Society of Plastics Engineers     

Ultrasonically initiated emulsion polymerization of n‐butyl acrylate

Ultrasonically initiated emulsion polymerization of n‐butyl acrylate (BA) without added initiator has been studied. The experimental results show that high conversion of BA can be reached in a short time by employing an ultrasonic irradiation technique with a high purge rate of N₂. The viscosity average molecular weight of poly(n‐butyl acrylate) (PBA) obtained reaches 5.24 × 10⁶ g mol^?1. The ultrasonically initiated emulsion polymerization is dynamic and complicated, with polymerization of monomer and degradation of polymer occurring simultaneously. An increase in ultrasound intensity leads to an increase in polymerization rate in the range of cavitation threshold and cavitation peak values. Lower monomer concentration favours enhancement of the polymerization rate. ¹H NMR, ¹³C NMR and FTIR spectroscopies reveal that there are some branches and slight crosslinking, and also carboxyl groups in PBA. Ultrasonically initiated emulsion polymerization offers a new route for the preparation of nanosized latex particles; the particle size of PBA prepared is around 50–200 nm as measured by transmission electron microscopy. © 2001 Society of Chemical Industry     

Preparation and characterization of polystyrene‐grafted attapulgite via surface‐initiated redox polymerization

Polystyrene‐grafted attapulgite (ATP‐g‐PS) was prepared using surface‐initiated redox initiation via graft from approach. ATP was modified with (3‐ aminopropyl) triethoxysilane (APTES) to anchor amine on the surface (ATP‐NH₂), and then ATP‐NH₂ was further treated with 4‐(diethylamino) salicylaldehyde (DEAS) to give aromatic tertiary amine groups functional ATP (ATP‐ATA). Subsequently, the surface‐initiated redox polymerization of styrene in the presence of ATP‐ATA and benzoyl peroxide (BPO) was performed to afford ATP‐g‐PS . The chemical grafting of PS on the surface of ATP was confirmed by Fourier transform infrared spectroscopy, X‐ray photoelectron spectroscopy, and thermogravimetric analysis . The crystal structure of PS‐grafted ATP was characterized by X‐ray diffraction (XRD) analysis. The morphology of ATP‐g‐PS was observed by scanning electron microscopy (SEM) . POLYM. ENG. SCI., 55:889–895, 2015. © 2014 Society of Plastics Engineers     

Surface modification of polyamide TFC membranes via redox‐initiated graft polymerization of acrylic acid

In this work, the redox‐initiated graft polymerization of acrylic acid (AA) onto the surface of polyamide thin film composite membranes has been carried out to enhance membrane separation and antifouling properties. The membrane surface characteristics were determined through the attenuated total reflection Fourier transform infrared spectra, scanning electron microscopy, atomic force microscopy, and water contact angles. The membrane separation performance was evaluated through membrane flux and rejection of some organic compounds such as reactive red dye (RR261), humic acid, and bovine serum albumin in aqueous feed solutions. The experimental results indicated that the membrane surfaces became more hydrophilic and smoother after grafting of AA. The modified membranes have a better separation performance with a significant enhancement of flux at a great retention. The fouling resistance of the modified membranes is also clearly improved with the higher maintained flux ratio and the lower irreversible fouling factor compared to the unmodified one. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45110.     

Preparation and properties of polymer-encapsulated phthalocyanine blue pigment via emulsion polymerization

Polymer-encapsulated phthalocyanine blue pigment dispersion was prepared with a polymerizable dispersant by emulsion polymerization method, and the effect of preparation conditions on the particle size of dispersion was investigated. Dynamic light scattering measurement demonstrated that allyloxy nonyl-phenoxypropanolpolyoxyethyleneetherammonium sulfonate (ANPS) was suitable for phthalocyanine blue pigment modification. The polymer-encapsulated phthalocyanine blue pigment dispersion with the small particles was obtained when the mass ratio of ANPS to phthalocyanine blue pigment, styrene (St) to phthalocyanine blue pigment, and ammonium persulfate (APS) to St was about 0.2, 0.2, and 0.01, respectively. Transmission electron microscopy (TEM), Fourier transforms infrared spectra (FTIR) and thermogravimetric analyses (TGA) provided supporting evidences for the encapsulation of phthalocyanine blue pigment with the formed copolymer. The polymer-encapsulated phthalocyanine blue pigment dispersion showed excellent stabilities to freeze–thaw treatment and centrifugal force.     

Preparation of a self‐compatibility alloy via a seed‐graft concentrated‐emulsion pathway

A novel polymerization procedure, the concentrated‐emulsion graft polymerization of styrene monomer with poly(butyl acrylate) seed, was proposed for the production of a self‐compatibility macromolecule alloy. The effects of the butyl acrylate content, sodium dodecyl sulfate concentration, and polymerization temperature on the graft ratio were investigated. Scanning electron microscopy, transmission electron microscopy, and impact strength were used to characterize the microstructure and mechanical performance of the self‐compatibility macromolecule alloy. The results showed that increasing the butyl acrylate content, reducing the sodium dodecyl sulfate concentration, and improving the polymerization temperature all favored an increased graft ratio, which resulted in increased impact strength of the self‐compatibility macromolecule alloy. Therefore, the concentrated‐emulsion polymerization method is particularly suitable for seed‐graft polymerization. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 2915–2920, 2002; DOI 10.1002/app.10288     

Thermoplastic acrylic resin with self‐healing properties

This article presents a novel processing method of a self‐healing acrylic thermoplastic material starting from a healing agent in solution form. The self‐healing system consisted of a solution of the healing agent dicyclopentadiene (DCPD) in dimethylformamide (DMF) and a solution of the catalyst bis(tricyclohexylphosphine) benzylidene ruthenium (IV) dichloride (called Grubbs' catalyst) in dichloromethane (DCM). Hollow glass tubes filled with the self‐healing components were incorporated into autopolymerizing acrylic resins. The one set of tubes was filled with a solution of DCPD (containing the dye Rhodamine B as a marker) and the other set with a solution of Grubbs' catalyst in dichloromethane. FTIR and DSC analyses revealed that a poly(DCPD) film formed at the healed interface. The low energy impact tests of the samples showed a recovery of 83% after 4 days. The benefits of the Grubb's catalyst solution are twofold; besides the repair of the cracks, which is common for such a system, the reaction could decrease the content of residual monomer in the acrylic resin, which could reduce diffusion of residual monomer out of the resins. POLYM. ENG. SCI., 56:251–257, 2016. © 2015 Society of Plastics Engineers     

交联型聚丙烯酸酯压敏胶乳液的合成及其粘接性能的研究

利用功能单体的自交联作用,采用种子半连续乳液聚合的方法进行多元共聚,合成了兼具较高剪切强度和剥离强度的交联型聚丙烯酸酯压敏胶乳液。运用DSC、DMA及粘接性能测试分别考察了聚合物的玻璃化转变温度、动态力学性能和压敏胶粘性能,并分析讨论了三者之间的相互关系。结果表明:功能单体所产生适度交联作用能较好地协调聚合物的内聚力和粘合力之间的平衡,使其具有较好的粘接及力学性能。聚合物的Tg、粘弹性等物理参数可用于评估其内聚力及粘接强度。     

pH and organic solvent‐sensitive properties of crosslinked polymeric spheres formed by a soap‐free emulsion polymerization

Narrowly distributed poly (styrene‐co‐(4‐vinylpyridine)) microspheres are facilely prepared by a soap‐free emulsion polymerization, and their structures and properties are investigated by TEM, FTIR spectra, DSC, and DLS, respectively. The sizes and glass transition temperatures of the polymeric spheres increase with an increase of 4‐vinylpyridine in the reactive system. In addition, these polymeric spheres show good stability in water and a series of organic solvents due to their crosslinked structures. When poly(styrene‐co‐(4‐vinylpyridine)) microspheres are obtained in the reactive system where the weight ratio of 4‐vinyl pyridine to styrene is less than 4/6, they can be well dispersed in water as well as in organic solvents such as ethanol, toluene and DMF, and show obvious pH sensitive and organic solvent‐sensitive characteristics. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

无皂乳液聚合制备丁二烯-丙烯腈橡胶

采用硫酸盐类可聚合乳化剂烯丙氧基壬基苯氧基丙醇聚氧乙烯醚硫酸铵（KD SE-10）通过低温乳液聚合法制备无皂丁腈橡胶。详细考察了可聚合乳化剂用量对门尼粘度、结合丙烯腈含量、凝胶量、拉伸强度、相对分子质量的影响情况,并确定了KD SE-10用量为2.7%～3.0%（质量分数）。制得的无皂丁腈橡胶相比普通丁腈橡胶具有显著的高强度、更优良的耐油性、相对分子质量分布窄的特点。     

Preparation and characterization of polyhydroxyurethane/silica nanocomposites via in situ surface‐initiated polymerization

The polyhydroxyurethane/silica nanocomposite (PHU/SN) was prepared by the in situ surface‐initiated polymerization of a five‐membered cyclic carbonate, 2,2‐bis[p‐(1,3‐dioxolan‐2‐one‐4‐yl‐methoxy)phenyl]propane (B5CC) and hexamethylene diamine, from the surfaces of the aminopropyl silica nanoparticles (APSN) for the first time. The percentage of grafting (PG%) and the grafting efficiency (GE%) of 27% and 19% were calculated from the results of thermogravimetric analysis (TGA), respectively, after the free polyhydroxyurethane was washed off. The chemical grafting of the polymer was also confirmed using Fourier transform infrared (FTIR) and the morphology of the silica nanoparticles in the nanocomposite was characterized by transmission electron microscope (TEM). POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers     

Preparation of acrylic/acrylate copolymeric surfactants by emulsion polymerization used in pesticide oil‐in‐water emulsions

In this work, acrylic/acrylate copolymeric surfactants, which can be used in the preparation of pesticide oil‐in‐water emulsions (EW), were synthesized by emulsion polymerization, using potassium persulfate (K₂S₂O₈) as an initiator, dodecyl mercaptan (DDM) as a chain transfer agent at the temperature range of 82–85°C. When the weight ratio of monomers was m(butyl acrylate) : m(methyl methacrylate) : m(acrylic acid) = 4 : 4 : 1.6 and the dosage of DDM was 2% (percentage of monomer mass), the prepared acrylic/acrylate copolymeric surfactants had a number‐average molecular weight of 2.5 × 10⁴ and exhibited good stability for pesticide EW. The carboxylic group distribution studies show that only the surface carboxylic groups make dispersed pesticide oil droplets more stable. The acrylic/acrylate copolymeric surfactants prepared by shot‐monomer had the most surface carboxylic group distribution (46.6%). To obtain greater surface carboxylic group distribution, maleic anhydride (MA) was used to modify the polymer system. Adding 2% MA (percentage of monomer mass) to the polymerization system, the surface carboxylic groups were increased 12% over unmodified acrylic/acrylate copolymeric surfactants. Compared with traditional pesticide EW, the avermectin EW prepared with acrylic/acrylate polymeric surfactant had much better stability. Meanwhile, its pesticide effect was similar to that of a control (1.8% abamectin emulsifiable solution). © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

乳聚三元共聚橡胶的制备及单体配比对聚合物结构和性能的影响

通过乳液聚合合成了苯乙烯-异戊二烯-丁二烯三元集成橡胶(E-SIBR),通过红外和核磁测试对产品进行表征,并详细研究了聚合过程中单体配比的变化对聚合物微观结构单元组成、相对分子质量分布、玻璃化转变温度以及物理机械性能的影响。     

Preparation and characterization of high efficiency ion‐exchange crosslinked acrylic fibers

Commercial acrylic fiber samples were first pretreated with hydrazine under various concentrations to give crosslinked structure. Then, the crosslinked fiber samples with different degree of crosslinking were treated with hydroxylamine hydrochloride to develop ion‐exchange fibers. These fibers contain amidoxime, amine, amide, and hydrazide groups simultaneously. The effects of reaction conditions on physical properties, thermal characteristics, surface morphology, ion adsorption quantity, and reusability were investigated. The results show that by increasing the reaction time, temperature, and concentration of hydroxylamine hydrochloride, the content of amidoxime groups in all samples were increased, but with noncrosslinked fibers noticeable drop in the mechanical properties were observed, while in crosslinked sample prepared under optimum conditions of reaction, good ion adsorption capacity with keeping mechanical properties was achieved. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 2202–2209, 2006     

Multifunctional,pH‐responsive graft copolymer prepared from deproteinized natural rubber and 4‐vinylpyridine via emulsion polymerization

We investigated the synthesis of a pH‐responsive graft copolymer of natural rubber and 4‐vinylpyridine. The grafting reaction was carried out using deproteinized natural rubber (DPNR) latex, with potassium persulfate as a free radical initiator. The pH responsiveness of the graft copolymer was investigated using water swelling and contact angle measurements, and was compared with that of pure DPNR. The graft copolymer was found to become responsive in solution at a pH of around 4. Indigo carmine adsorption studies identified the Langmuir isotherm, suggesting monolayer coverage. The adsorbed indigo carmine, a model anionic drug, and carbon dots, an emerging nanosized fluorophore, could be released from the graft copolymer by lowering the pH of the solution. The graft copolymer was tested as a heavy metal adsorbent, and demonstrated selectivity to copper(II) ions. The graft copolymer of 4‐vinylpyridine and DPNR developed in this study is therefore a multifunctional, pH‐responsive material with a wide range of potential applications, including sensing and catalysis, as a biomedical material and as an adsorbent. © 2017 Society of Chemical Industry     

Characterization of molecular structure of acrylic copolymers prepared via emulsion polymerization using A4F‐MALS technique

The study is primarily focused on the possibility to utilize organic asymmetric flow field‐flow fractionation (A4F) coupled to a multi‐angle light scattering (MALS) detector for the characterization of copolymers of methyl methacrylate with various acrylates prepared by emulsion polymerization. The effects of acrylate monomer type and content on the molar mass distribution and degree of branching of acrylic copolymers have been studied by A4F‐MALS using tetrahydrofuran as a carrier solvent. It has been found that the growing amount of acrylate results in the increase of molar mass, polydispersity, and branching degree as a result of chain transfer to polymer. Highly branched compact macromolecules with ultra‐high molar mass were identified in all copolymers containing a high level of acrylate. In contrast to size traditionally used exclusion chromatography, organic A4F‐MALS has been proved as a very efficient technique for the characterization of high molar mass acrylic emulsion copolymers. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40995.