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1.
Self-crosslinking fluorinated polyacrylate latexes based on butyl acrylate (BA), fluorine monomer octafluoropentyl methacrylate (OFPMA), self-crosslinking functional monomers acrylic acid (AA) and 2-hydroxyethyl acrylate (HEA) were synthesized by a monomer-starved seeded semi-continuous emulsion polymerization process. The latexes and their corresponding films were characterized by laser particle size analyser, Fourier transform infrared (FTIR) spectroscopy, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), contact angle goniometer, X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM). Results indicated that the particle size of the latexes and the gel content of the films were both independent of the amount of OFPMA employed. On the other hand, the particle size of the latexes decreased and the gel content of the films increased with the incorporation of AA and HEA as expected. Glass transition temperature (Tg) and the thermal stability of the copolymer were both improved gradually as OFPMA content increased. XPS, AFM and water contact angle measurement indicated that the fluoroalkyl groups had a tendency to enrich on the surface of the films. However, this enrichment of fluorine on the film surface was reduced after the introduction of self-crosslinking functional monomers into the system. Finally, the adhesive property of the latexes was evaluated for application as a pressure sensitive adhesive (PSA).  相似文献   

2.
Cationic copolymer emulsions of St, BA, AA, and GMA were successfully synthesized via semi‐continuous emulsion polymerization. The properties of synthesized cationic emulsions were characterized by monomer conversion and solid content, differential scanning calorimeter, particle size and distribution, zeta potential, and centrifugal stability. The film performance of the cationic emulsions formed on cotton fiber surface was observed by scanning electricity microscopy. The influence of cationic emulsions on the color data, K/S values and rubbing fastness of dyed cotton fabrics was also investigated. The results show that P (St‐BA‐AA‐GMA) emulsion had larger particle size and higher zeta potential than P (St‐BA‐AA) emulsion. When the films were formed at room temperature, P (St‐BA‐AA‐GMA) emulsion film had better performance than P (St‐BA‐AA) emulsion film. The addition of GMA monomers improved the film performance. P (St‐BA‐AA‐GMA) emulsion films formed at 120 °C after acetic acid solution treatment had the best water resistance. Dyed cotton fabrics pretreated with P (St‐BA‐AA‐GMA) emulsion had better pigment dyeing performance than those pretreated with P (St‐BA‐AA) emulsion. It demonstrates that the addition of GMA monomers further improved the effect of pigment dyeing for cotton fabrics with cationic emulsions as binders. With the increase of P (St‐BA‐AA‐GMA) concentration, the color performance of dye fabrics improved while the rubbing fastness decreased a little. But, the handle and fastness still meets the use standards for consumers. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44987.  相似文献   

3.
Results are presented on the preparation and characterization of batch emulsion copolymers of butyl methacrylate and glycidyl methacrylate (GMA). The two main problems occurring during an emulsion copolymerization with GMA are partial hydrolysis of the epoxy groups and internal crosslinking of the latex particles formed. The influence of chain transfer agents (CTA) on the degree of crosslinking was investigated. Furthermore, the effect of reaction temperature and the addition of methacrylic acid on the sol/gel content of the polymer formed and on the rate of epoxy hydrolysis were investigated. It was found that lowering the reaction temperature did not increase the sol content; however, it significantly decreased the extent of hydrolysis. The addition of a CTA (especially CBr4) increased the sol content of the polymer, and good control over the molecular mass was achieved. The addition of methacrylic acid showed that this monomer can be used without any complications with respect to the control of the sol content of the polymer formed. © 1996 John Wiley & Sons, Inc.  相似文献   

4.
Film-forming polystyrene/poly(n-butyl acrylate-co-glycidyl methacrylate) [PS/P(BA-co-GMA)] core–shell latex particles were prepared via a two-stage emulsion polymerization procedure using a polystyrene latex seed. Delayed addition of GMA was used in order to locate functional epoxy groups close to the particle surfaces. It was found that a temperature of 25°C at the second-stage polymerization, in combination with a redox initiator system, was essential for the formation of a uniform shell of BA–GMA copolymer around the PS core. The latex particle morphology was investigated by transmission electron microscopy (TEM). Reactive double bonds were introduced into the particle shells in order to produce a film-forming latex system that could be cured by ultraviolet (UV)-radiation without any need to use reactive multifunctional monomers or oligomers as crosslinkers. The surface-bound epoxy groups were used as grafting sites for amine or carboxyl functional unsaturated monomers, respectively. The grafting was demonstrated by Fourier transform infrared (FTIR) spectroscopy. Films prepared from modified and unmodified latexes were exposed to UV radiation in the presence of a photoinitiator. Crosslinking was tested by thermal mechanical analysis (TMA) and by determination of swelling and gel content of exposed films. It was demonstrated that films from the modified latexes after irradiation had significantly higher stiffness and gel content and showed lower swelling than unmodified ones. © 1996 John Wiley & Sons, Inc.  相似文献   

5.
The synthesis of immobilized β‐cyclodextrin derivatives onto polyamide‐6 fabric is presented. These novel fabrics were prepared by graft‐copolymerization of glycidyl methacrylate (GMA) onto polyamide 6 fabric, using a chemical redox system K2S2O8/CuSO4·5H2O, followed by reaction of β‐cyclodextrins (CD) or monochlorotriazinyl (MCT β‐CD) with the GMA epoxy group. Some biocidal guests were complexed into CD cavity including p‐hydroxy benzoic acid, AgNO3–ethanolamine mixture, iodine, N,N‐diethyltoluamide (DETA), citronella, jasmine, and sweet basil. Characterization of the novel fabrics was done by Fourier transform infrared spectroscopy (IR), electron scanning microscopy (SEM), and thermo gravimetric analysis (TGA). The biocidal activity of the grafted fabrics was tested against five strains of microorganisms. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 2586–2593, 2006  相似文献   

6.
Negative photoresists are materials that become insoluble in developing solution when exposed to optical radiation. This work describes the production of simple negative‐working resists, demonstrating aqueous development, for potential printing plate applications. The copolymers comprised glycidyl methacrylate (GMA) and acrylic acid (AA) via free‐radical solution polymerization in methyl ethyl ketone as a solvent using azobisisobutyronitrile as initiator at 60°C. Characterization of the copolymers prepared was carried out via IR, 1H‐NMR, and thermal analysis techniques. The copolymers of GMA/AA were successfully prepared over a wide range of composition. It was found that the copolymer containing 15 mol % of AA unit in the feed was developed with NaOH on copper plate rather than zinc plate and crosslinked in the presence of photogenerated acid (PAG) caused by acid‐initiated ring‐opening polymerization of pendant epoxide groups. Exposure of the resist films to UV radiation at λmax = 365 nm results in the generation of acid, and the subsequent baking process at 80°C for 1 min promotes the diffusion of the PAG, which initiates the cationic crosslinking of the epoxide rings. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   

7.
Thermosetting acrylic latexes were synthesized using butyl acrylate (BA), methyl methacrylate (MMA), 2-hydroxyethyl methacrylate (HEMA), and methacrylic acid (MAA) via seeded two-stage process. A 2-level factorial experimental design was employed to investigate the effect of hydroxyl (core phase), carboxylate (shell phase) groups, and type of surfactant (Triton X200, Tergitol XJ) on the mechanical properties of thermosetting latexes. Eight latexes with varying concentration of HEMA, MAA and two types of surfactants were synthesized and crosslinked with three crosslinkers. Latex functionality for crosslinking was located in the core only, the shell only, and both the core–shell with varying concentrations. Melamine-formaldehyde (hexamethoxymethyl melamine) resin was employed to crosslink hydroxyl functionalities in the core. Carboxylic acid groups in the shell were crosslinked with zinc ammonium carbonate. HDI isocyanurate (Desmodur N3300A) were used to crosslink with hydroxyl or carboxyl functional groups in core and shell. The mechanical properties of coatings were evaluated in terms of tensile properties, cross-hatch adhesion, pencil hardness, and impact resistance. Design of experiment (DOE) was utilized to investigate the effect of variables on mechanical properties of crosslinked thermoset films.  相似文献   

8.
A novel macromonomer containing fluorinated units (PHFBMA‐GMA) was synthesized through a two‐step procedure: firstly, hexafluoro‐butyl methacrylate (HFBMA) was polymerized in the presence of functional chain transfer agent 3‐mercaptopropionic acid (MPA) and then the carboxyl acid group terminated polymer was end‐capped with glycidyl methacrylate (GMA). Chemical structures of PHFBMA‐GMA were characterized by gel permeation chromatography, fourier transform infrared spectroscopy (FTIR), and 1H nuclear magnetic resonance (NMR). Subsequently, PHFBMA‐GMA was employed as reactive surface additives added into UV‐cured polyacrylate to modify UV‐curable coatings. It is convenient to control the tail length of the fluorinated segments in this study by adjusting the ratio of initiator and chain transfer agent. The influence of both the concentration and the molecular weight of PHFBMA‐GMA on the surface properties of UV‐cured films was investigated. With increasing both the concentration and the molecular weight of PHFBMA‐GMA, the surface energy of the UV‐cured films decreased. X‐ray photoelectron spectroscopy was employed to characterize and quantify the surface composition and the results confirm the enrichment of fluorinate atoms on the surface. Moreover, the physical properties of UV‐cured films, such as gel content, water absorption, pencil hardness, adhesion, chemical resistance, mechanical properties, optical transmittance, and thermal properties, were also investigated in detail. The novel macromonomer was economical but effective to modify the properties of the UV‐curable coatings. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43116.  相似文献   

9.
In this study stable latexes of butyl acrylate (BA)/methyl methacrylate (MMA)/diacetone acrylamide (DAAM) copolymers and BA/MMA/vinyl neo-decanoate (VeoVa-10)/DAAM copolymers were synthesized by a modified semi-continuous microemulsion copolymerization. Ammonium persulfate was used as initiator and a redox system for post-polymerization to reduce the free monomers content. Methacrylic acid (MMA), 2-acrylamido-2-methylpropane sulfonic acid (AMPS), acrylic acid (AA) and various “green” industrial anionic, non-ionic and anionic polymerizable surfactants free of alkylphenol ethoxylates (APEO free) were tested as a stabilizing system. The resulting latexes, their corresponding self-1K crosslinkable binder using the adipic acid (ADH) dihydrazide as crosslinking agent and their films were characterized with rotational viscometer, dynamic light scattering, gloss, dynamic mechanical analysis, minimum film forming temperature (MFFT), water resistance and swelling in methyl ethyl ketone measurements. The experiments showed that BA\MMA\VEOVA-10\DAAM latexes prepared with methacrylic acid and a polymerizable surfactant showed zero coagulation during polymerization. Their corresponding 1K crosslinkable binder with ADH were stable over 6 months storage time and showed good all around properties that makes them suitable for use in friendly to the environment coatings.  相似文献   

10.
Glycidyl methacrylate functionalized acrylonitrile–butadiene–styrene (ABS‐g‐GMA) particles were prepared and used to toughen polylactide (PLA). The characteristic absorption at 1728 cm?1 of the Fourier transform infrared spectra indicated that glycidyl methacrylate (GMA) was grafted onto the polybutadiene phase of acrylonitrile–butadiene–styrene (ABS). Chemical reactions analysis indicated that compatibilization and crosslinking reactions took place simultaneously between the epoxy groups of ABS‐g‐GMA and the end carboxyl or hydroxyl groups of PLA and that the increase of GMA content improved the reaction degree. Scanning electron microscopy results showed that 1 wt % GMA was sufficient to satisfy the compatibilization and that ABS‐g‐GMA particles with 1 wt % GMA dispersed in PLA uniformly. A further increase of GMA content induced the agglomeration of ABS‐g‐GMA particles because of crosslinking reactions. Dynamic mechanical analysis testing showed that the miscibility between PLA and ABS improved with the introduction of GMA onto ABS particles because of compatibilization reactions. The storage modulus decreased for the PLA blends with increasing GMA content. The decrease in the storage modulus was due to the chemical reactions in the PLA/ABS‐g‐GMA blends, which improved the viscosity and decreased the crystallization of PLA. A notched impact strength of 540 J/m was achieved for the PLA/ABS‐g‐GMA blend with 1 wt % GMA, which was 27 times than the impact strength of pure PLA, and a further increase in the GMA content in the ABS‐g‐GMA particles was not beneficial to the toughness improvement. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   

11.
This work presents data on human immunoglobulin G (HIgG) adsorption onto L ‐arginine ligand attached poly(GMA/MMA/EGDMA)‐based affinity beads which were synthesized from methyl methacrylate (MMA) and glycidiyl methacrylate (GMA) in the presence of a crosslinker (i.e., ethylene glycol dimethacrylate; EGDMA) by suspension polymerization. The epoxy groups of the poly(GMA/MMA/EGDMA) beads were converted into amino groups after reaction with ammonia or 1,6‐diaminohexane (i.e., spacer‐arm). With L ‐arginine as a ligand, it was covalently immobilized on the aminated (poly(GMA/MMA/EGDMA)‐ AA) and/or the spacer‐arm attached (poly(GMA/MMA/EGDMA)‐SA) beads, using glutaric dialdehyde as a coupling agent. Both affinity poly(GMA/MMA/EGDMA)‐based beads were used in HIgG adsorption/desorption studies under defined pH, ionic strength, or temperature conditions in a batch reactor, using acid‐treated poly(GMA/MMA/EGDMA) beads as a control system. The poly(GMA/MMA/EGDMA)‐SA affinity beads resulted in an increase in the adsorption capacity to HIgG compared with the aminated counterpart (i.e., poly(GMA/MMA/EGDMA)‐AA). The maximum adsorption capacities of the poly(GMA/MMA/EGDMA)‐AA and poly(GMA/MMA/EGDMA)‐SA affinity beads were found to be 112.36 and 142 mg g?1, and the affinity constants (Kd), evaluated by the Langmuir model, were 2.48 × 10?7 and 6.98 × 10?7M, respectively. Adsorption capacities of the poly(GMA/MMA/EGDMA)‐AA and poly(GMA/MMA/EGDMA)‐SA were decreased with HIgG by increasing the ionic strength adjusted with NaCl. Adsorption kinetic of HIgG onto both affinity adsorbents was analyzed with first‐ and second‐order kinetic equations. The first‐order equation fitted well with the experimental data. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 672–679, 2007  相似文献   

12.
A series of waterborne epoxy latexes was synthesized, and epoxy/(silica sol) composite latexes were prepared. The effects of functional monomer methacrylic acid (MAA) and silica sol on the latex particle size, morphology, and stability were investigated. With increasing amounts of MAA, the conversion rate increased, the particle size reduced, and the viscosity of the epoxy latexes increased. The epoxy latexes had storage stability and could be stored at room temperature for more than 6 months with a solid content variation of less than 1%. For the (silica sol)‐modified waterborne epoxy latexes, the effects of preparation techniques and silica sol content on the latexes and latex films were investigated. When the silica sol content increased, the particle size of the composite latexes decreased. The morphology investigation showed that when the silica sol content increased, the uneven surface level of the latex films was increased. The increase of elemental silica on the surface was in accord with the improvement of the water resistance of the composite latex films. The heat resistance of these films was improved as well, and their overall performance was better than that of the epoxy latex films. J. VINYL ADDIT. TECHNOL., 20:57–64, 2014. © 2014 Society of Plastics Engineers  相似文献   

13.
Jute fabric was modified using acrylic acid (AA) as the finishing agent in the presence of K2S2O8 and Na3PO4 catalysts separately or in selected combinations, employing a pad–dry–cure technique. Treatment with 10% acrylic acid at 30°C and at pH 7 produced optimum effects: a batching time of 45–60 min at 30°C, followed by drying of the batched fabric at 95°C for 5 min and curing of the dried fabric at 140°C for 5 min produced most balanced improvements in the textile related properties. Na3PO4 catalyst allowed esterification of AA with cellulosic, hemicellulosic, and lignin constituents of jute, and K2S2O8 catalyst allowed radical polymerization of free acrylic acid or jute-bound acrylic acid moieties; the said processes ultimately lead to some degree of crosslinking of the chain polymers of jute. Examination of the surface morphology of untreated and treated jute fabrics by scanning electron microscopy revealed a good degree of masking effect on the unit cells of jute and intercellular regions by a cohesive film of polyacrylic acid or its salts, particularly when K2S2O8 was used either alone or in combination with Na3PO4 as catalyst. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 68:63–74, 1998  相似文献   

14.
Hydrogenated rosin epoxy methacrylate (HREM), based on hydrogenated rosin and glycidyl methacrylate (GMA), was synthesized for use as an advanced tackifier in the UV‐crosslinking pressure sensitive adhesives (PSAs) system. The HREM, as a tackifier, contained UV‐curing sites; thus, allowed photopolymerization to occur by UV irradiation. This UV‐curable tackifier, HREM, can improve the curing rate and adhesion performance of UV‐crosslinking PSAs. The characteristics of HREM were analyzed by GPC and DSC and its synthetic mechanism studied using FTIR and 1H NMR; the characteristic peaks of hydrogenated rosin and GMA vanished, but new peaks for HREM appeared. The PDI and the Tg by DSC were 1 and ?25.6°C, respectively. The photopolymerization of HREM was studied using photo‐DSC. Heat flow was observed during UV irradiation, and the curing rate and conversion both increased with rising photoinitiator content. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   

15.
摘要:以丙烯酸丁酯(BA)、甲基丙烯酸甲酯(MMA)、丙烯酸羟乙酯(HEA)为主要单体,桐油酸和甲基丙烯酸缩水甘油酯(GMA)为功能性单体,采用半连续乳液聚合法制备了一系列桐油酸改性含环氧基团聚丙烯酸酯乳液(简称改性聚丙烯酸酯乳液)。通过FTIR表征胶膜的结构,同时测定了胶膜的力学性能、耐酸耐碱性等。结果表明:当桐油酸添加量(以MMA、BA、HEA、GMA的总质量为基准)为4%时,随着GMA含量(即GMA的质量占总丙烯酸单体质量的百分数,下同)的增加,胶膜铅笔硬度增大,耐水、耐酸碱性能增强,拉伸强度增大,热稳定性增加,胶膜附着力增加。当GMA含量为12%时,胶膜铅笔硬度为4H,涂在马口铁上的胶膜在5%的盐酸溶液中浸泡144 h无变化,在5%的氢氧化钠溶液浸泡72 h无变化,24 h的吸水率为3.31%,附着力为0级。  相似文献   

16.
Polymer grafting is a well-known method for surface modification. It improves the interfacial adhesion of the particle with the epoxy. In this study, aluminum oxide (Al2O3) was functionalized with vinyltriethoxysilane (VTES) to graft the carbon double bond for further polymerization. Then, glycidyl methacrylate (GMA) was polymerized to graft poly(glycidyl methacrylate) (PGMA) onto the surface of Al2O3 using the carbon double bond grafted in the previous step. Finally, 4.4′-diaminodiphenylmethane (DDM) was applied to bridge epoxide groups contained in the PGMA and the matrix. Consequently, the thermal conductivity of the composites increased about 320%.  相似文献   

17.
The graft copolymerization of glycidylmethacrylate (GMA) onto modified nylon‐6 fibers containing polydiallyldimethylammonium chloride (PDADMAC) groups in the presence of (Cu 2+–K2S2O8) as a redox initiating system was carried out, with very high extent and almost without homopolymer formation. The mechanism of the graft polymerization induced by this system was suggested. The rate of grafting was determined by varying the monomer, K2S2O8, and cupric ion concentrations as well as the amount of PDADMAC. The kinetic investigation revealed that the rate of grafting (Rp) of GMA onto modified nylon‐6 fibers is proportional to [GMA]1.83, [CuSO4·5H2O]0.46, [PDADMAC]0.4, and [K2S2O8]1.43. The overall activation energy was 134.7 kJ/mol. The fine structure and thermal properties of the grafted nylon‐6 fibers were investigated. investigated. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 613–618, 2006  相似文献   

18.
周威  傅和青  颜财彬  陈焕钦 《化工学报》2013,64(6):2291-2299
引言水性聚氨酯相对溶剂型聚氨酯具有不燃、气味小、不污染环境等优点[1-2],从而广泛用于涂料[3]、胶黏剂[4]、油墨[5]等领域。目前,常用于软包装领域的薄膜主要是表面能很低的非极性膜,而水性聚氨酯胶黏剂具有较高的表面自由能,对非极性膜的润湿性差,因此需要降低水性聚氨酯的表面张力,达到润湿非极性膜的目的。  相似文献   

19.
Cotton fabric was converted into an ion exchanger by grafting it with (1) glycidyl methacrylate (GMA), followed by aminization with ethylene diamine; (2) dimethylaminoethyl methacrylate (DMAEMA), followed by quaternization; and (3) acrylic acid (AA). Grafting was carried out on a pilot scale using a thiocarbonate–H2O2 redox system. The so-obtained cotton graft copolymers were monitored for their ability to remove different dyes as well as heavy metals from aqueous solutions. It was found that the magnitude of dye exhaustion was as follows. For direct and reactive dyes the percentage of exhaustion follows the order of aminized GMA > quaternarized DMAEMA > DMAEMA, whereas for acid dye the percentage of exhaustion follows the order of quaternarized DMAEMA > DMAEMA > aminized GMA. On the other hand poly(AA)–cotton copolymer is very effective at removal of the basic dye. With respect to heavy metal ions removal, the copolymers show the following order: AA > aminized GMA > quaternarized DMAEMA > DMAEMA. While dichromate removal follows the order of quaternarized DMAEMA > DMAEMA > aminized GMA. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 68: 2151–2157, 1998  相似文献   

20.
Cardanol-based vinyl ester resin (CVER) was prepared by reacting indigenously synthesized cardanol-based epoxidized novolac resin (CENR) with methacrylic acid (MA) in the presence of triphenylphosphine as catalyst. Five samples of cardanol-based vinyl ester resin containing styrene and glycidyl methacrylate (GMA), as diluents, in the weight ratios 40:0, 30:10, 20:20, 10:30 and 0:40 were prepared at room temperature. Sharp exotherms were observed in DSC scans in the temperature range of 60–170 °C. The onset temperature (Tonset), peak exothermic temperature (Tp) and completion temperature (Tstop) decreased with increase in GMA content in the ternary blend systems of CVER/styrene/GMA. A broad exotherm was observed after the initial sharp exotherm that was attributed to the etherification reaction. Cured samples were found to be stable up to 205–235 °C and started loosing weight above this temperature. Rapid decomposition was observed in the temperature range of 400–550 °C as evidenced by TGA analysis. Increase of GMA content in ternary blend systems of CVER/styrene/GMA lowered the tensile strength progressively and enhanced the impact strength and elongation-at-break. The cured films of VER containing mixture of styrene and GMA exhibited good gloss and impact resistance. The chemical resistance of cured films of VER containing mixture of styrene and GMA showed good resistance to acids, deionized water, synthetic sea water and mineral turpentine oil.  相似文献   

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