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1.
Fluorinated polyacrylate latexes are preferably potential materials for use in the textile finishing due to their special surface property and especially economical, low-toxic characteristics compared to fluorinated polyacrylate solutions. A novel cationic fluorine-containing polyacrylate soap-free latex (CFMBD) with core-shell structure was accordingly developed by co-polymerizing dodecafluoroheptyl methacrylate (DFMA), methyl methacrylate (MMA), butyl acrylate (BA), and dimethylaminoethyl methacrylate (DM) using a cationic reactive emulsifier, maleic acid double ester-octadecyl poly(ethyleneoxy)20 ether-ethylene trimethyl ammonium chloride (R303). Then CFMBD was utilized to treat the cotton fabric. Results showed that the as-prepared latex had due structure and its particles had uniform spherical core-shell structure with an average diameter of 125 nm. The core-shell CFMBD latex film thus had two T g and its thermal property was improved due to the introduction of DFMA. CFMBD could form a smooth resin film on the treated fabric/fiber surface under FESEM observation. XPS analysis indicated the fluoroalkyl groups had the tendency to enrich at the film-air interface. Hydrophobicity of the CFMBD treated fabric was slightly superior to that of the fabric treated by general emulsion but their oleophobicity was identical. Contact angles of water and diiodomethane on the CFMBD treated fabric surface could attain 133.5 ° and 105.5 °, respectively. However, washing durability of the treated fabric by CFMBD showed improvement compared to the general emulsion. In addition, CFMBD didn’t influence whiteness of the treated fabric but would make it slightly stiff at high doses.  相似文献   

2.
Fluorosilicone modified polyacrylate emulsion was successfully synthesized via emulsifier-free emulsion polymerization using polymerizable surfactant and sol-gel process. TEM analysis indicated that the hybrid particles were spherical-like particles with narrow size distributions. The influence of synthetic conditions on the physical and chemical properties of fluorosilicone modified polyacrylate was investigated, including the mass ratio of methyl methacrylate (MMA)/butyl acrylate (BA) and the content of dodecafluoroheptyl methacrylate (DFMA) and ethyl silicate (TEOS). The water absorption decreased as the MMA/BA mass ratio was reduced from 5/4 to 2/4, then increased afterwards. With the reducing of MMA/BA mass ratio, the tensile strength decreased, while the elongation at break increased. The thermal stability of the hybrid film was improved with the increasing of TEOS amount. Finally, the contact angle results showed that the finished fabric had the excellent water repellency. Meanwhile, the SEM measurements confirmed that the finished fabric had the rough surface. XPS analysis demonstrated that there was a layer of fluorosilicone modified polyacrylate film covered on the finished fabric surface, and fluorinated segments had the tendency to be enriched at the film-air interface.  相似文献   

3.
Fluorinated polyacrylate latexes are preferably candidates for the textile water repellent finishes as a result of their special surface property and especially economical, low-toxic characteristics compared to fluorinated polyacrylate solutions. The benefits of soap-free latex prepared from reactive surfactants are now well known. We herein used a reactive emulsifier, ammonium allyloxtmethylate nonylphenol ethoxylates sulfate (DNS-86), to prepare novel self-crosslinking fluorinecontaining polyacrylate soap-free latex (FMBN) with core-shell structure by co-polymerization of dodecafluoroheptyl methacrylate (DFMA), methyl methacrylate (MMA), butyl acrylate (BA), and N-methylolamide (NMA), and then treated the cotton fabric with FMBN. Results showed that the as-prepared latex particles had the uniform spherical core-shell structure with an average diameter of 116 nm. FMBN could form a smooth resin film on the treated fabric/fiber surface under Field emission scanning electron microscopy (FESEM) observation, but some protuberances appeared on that surface from Atomic force microscopy (AFM) image. X-ray photoelectron spectroscopy (XPS) analysis indicated the fluoroalkyl groups tended to enrich at the film-air interface. Hydrophobicity of the FMBN treated fabric was superior to that of the fabrics treated by general emulsion and the non-crosslinking one. In addition, the above three latexes didn’t influence whiteness of the treated fabrics at all. However, they all, and in especial two self-crosslinking latexes would make the treated fabrics stiffer compared to non-crosslinking one.  相似文献   

4.
Monomer of acryloyl tri(1,1,2,2-tetrahydroperfluoro-octyl) citrate (FOC) and β-acryloyloxy 1,1,2,2-tetrahydroperfluoro-octyl propionate (FOP) were successfully synthesized and copolymerized with n-butyl acrylate by continuous process emulsion copolymerization. Thermal properties of resulting fluorinated copolymers were characterized by TGA. The water and oil repellency of the polymers used as textile finishing agent on cotton fabrics were investigated, and the surface energies were calculated. The X-ray photoelectron spectrometer (XPS) measurement showed strong surface enrichment of fluorinated segments.  相似文献   

5.
Poly(ethylene 2,6-naphthalate) (PEN)/Poly(ethylene glycol) (PEG) copolymers were synthesized by two step reaction during the melt copolymerization process. The first step was the esterification reaction of dimethyl-2,6-naphthalenedicarboxylate (2,6-NDC) and ethylene glycol (EG). The second step was the condensation polymerization of bishydroxyethylnaphthalate (BHEN) and PEG. The copolymers contained 10 mol% of PEG units with different molecular weights. Structures and thermal properties of the copolymers were studied by using1H-NMR, DSC, TGA, etc. Especially, while the intrinsic viscosities of PEN/PEG copolymers increased with increasing molecular weights of PEG, but the glass transition temperature, the cold crystallization temperature, and the weight loss temperature of the copolymers decreased with increasing molecular weights of PEG. Consequently, the hydrophilicities by means of contact angle measurement and moisture content of the copolymer films were found to be significantly improved with increasing molecular weights of PEG.  相似文献   

6.
We have synthesized a series of copolymers with different compositions of acrylonitrile (AN, 80–100 wt%), methyl acrylate (MA, 4–20 wt%) and itaconic acid (IA, 0–3 wt%) by using an efficient aqueous suspension polymerization, and have investigated the molecular structure and thermal stabilization behavior of PAN homopolymer, AN/MA-based bipolymers, and AN/MA/IA-based terpolymers by adopting 1H/13C-NMR and thermal FT-IR analyses. The viscosity-average molecular weight of the synthesized polymers were measured to be ~263,000 g/mol. The reactivity ratios of AN and MA for all the copolymers were evaluated to be 0.99 and 1.05, respectively. Accordingly, the output compositions of the synthesized copolymers were quite consistent with the input monomer compositions. The 13C NMR analysis revealed that all the synthesized polymers have an atactic chain configuration, regardless of the feed composition. The structural evolutions during the thermal stabilization process of the copolymers in air environment were characterized by monitoring the temperature-dependent changes of characteristic absorbance bands at 2240 cm-1 (C≡N), 1595 cm-1 (C=N) and 1660 cm-1 (C=O) with aid of thermal FT-IR spectroscopy. It was found that the IA unit in the terpolymers accelerated the oxidation and cyclization reactions, unlike the retarding effect of MA unit, and that the onset temperatures of the oxidation reaction of the copolymers with IA unit was lower than that of the cyclization reaction.  相似文献   

7.
The new copolymers from different feed compositions of glycidyl methacrylate (GMA) and tetrahydrofurfuryl acrylate (THFA) were synthesized using free radical polymerization in toluene at 70±1 °C using benzoyl peroxide (BPO) as initiator. The polymers were characterized by 1H NMR, 13C NMR and FTIR spectroscopic techniques. The polydispersities of the copolymers suggest a strong tendency for chain termination by disproportionation. The glass transition temperature of the copolymers increases with increase in GMA content. The thermal stability of the copolymers increases with increase in THFA content. The copolymer compositions were determined using 1H NMR analysis. Reactivity ratios for GMA and THFA as determined by the Mao-Huglin method were r1=0.379 and r2=0.266. The results showed that all these copolymerizations are strictly linear systems describable by the Mayo-Lewis equation based on the terminal model and that accurate reactivity ratio data can be obtained.  相似文献   

8.
Nylon 4/6 copolymers based on 2-pyrrolidone (C4) and ε-caprolactam (C6) were synthesized and characterized as part of ongoing efforts to develop thermally stable, melt-processable 2-pyrrolidone (C4) based Nylons. Copolymers of various compositions were synthesized at between 50 and 100 °C via the anionic ring opening polymerization of C4 and C6 using a potassium tert-butoxide catalyst and a benzoyl chloride initiator. The polymers were characterized by NMR spectroscopy, DSC, TGA, GPC, intrinsic viscosity measurements, and X-ray scattering (SAXS and WAXS). Their chemical compositions and sequence distributions were obtained by 1H- and 13C-NMR spectroscopies, respectively. X-ray scattering was used to investigate the lamellar morphologies and the crystal structures of solvent cast films of the copolymers. WAXS revealed the presence of α-phase crystals in the copolymers. TGA data coupled with molecular weight and sequence distribution information indicated that the polymers’ thermal stability depended on both their chemical composition and their sequence distribution.  相似文献   

9.
The core-shell monodisperse P(St-MAA) microspheres with different diameters ranging from 200 nm to 400 nm were prepared by soap-free emulsion copolymerization, in which styrene (St) and methacrylic acid (MAA) were polymerizable monomers, and ammonium persulfate (APS) acted as initiator. The diameters and monodispersity of P(St-MAA) microspheres could be controlled by adjusting the concentrations of styrene, methacrylic acid and ammonium persulfate. The core-shell structure and chemical component distribution of the P(St-MAA) microspheres were confirmed by TEM and XPS. The photonic crystals on polyester fabrics with three-dimensionally ordered arrangement were fabricated by self-assembly of gravitational sedimentation with P(St-MAA) microspheres and exhibited brilliant structural colors without any chemical dyes and pigments. SEM, TEM and crystallographic analysis were applied to confirm a face centered cubic (fcc) structure of the photonic crystals on polyester fabrics. The versatile structural colors of the photonic crystals were dependent on the photonic band-gap which could be regulated by the spherical size of P(St-MAA) microspheres and viewing angles. This technology may provide a new strategy to color the fabrics and reduce the pollution in the current textile industry.  相似文献   

10.
The research work was carried out to synthesize a series of novel chitosan based water dispersible polyurethanes (CS-WDPUs). The three step synthesis involves the formation of end capped PU-prepolymer was formed through the reaction between polyethylene glycol (PEG) (Mn=600 g/mole, dimethylolpropionic acid (DMPA) and isophorone diisocyanate (IPDI) followed by the preparation of neutralized NCO terminated PU-prepolymer, which lead to the chain extension by using the chitosan. The dispersion of the obtained product was carried out by adding proper proportion of water. The synthesized CS-WDPUs were applied onto the different qualities of plain weave poly-cotton printed and dyed textile swatches by employing pad-dry-cure procedures. The textile assets of the treated and untreated textile swatches were assessed, as color fastness, pilling resistance, tear and tensile strength. The results showed that the chitosan incorporation into PU backbone has significant effect on the assets of treated textiles. These synthesized CS-WDPUs are eco-friendly bio-based finishes with potential applications for polyester/cotton textiles.  相似文献   

11.
Hydrophilic and water-insoluble poly(acrylonitrile-co-methyl methacrylate) [P(AN-co-MMA)] nanoparticles were prepared to investigate their moisture-absorbing heat release effect. The nanoparticle size was controlled by varying the composition of AN and MMA. First, P(AN-co-MMA) nanoparticles were synthesized by emulsion polymerization, followed by cross-linking with hydrazine for water insolubility. Secondly, the hydrazine-cross-linked P(AN-co-MMA) nanoparticles were hydrolyzed in an aqueous NaOH solution to form hydrophilic groups. The hydrolyzed and cross-linked P(AN-co-MMA) [hc-P(AN-co-MMA)] nanoparticles had a more uniform and smaller particle size with increasing MMA content compared to the PAN nanoparticles, this is due to decreasing polar nitrile groups in the P(AN-co-MMA) with MMA content. A nanoparticle size less than 45 nm was obtained for P(AN-co-MMA) with a 20 mol% MMA content. The hc-P(AN-co-MMA) nanoparticles showed a temperature rise maximum of up to 12.9 °C in the moisture-absorbing heat release test. In addition, when the nanoparticles with 20 mol % MMA content were coated on cotton fabrics, the temperature of the fabrics increased by up to 7.8 °C at 90 % relative humidity. This demonstrates that the nanoparticles can be applied as a potential moisture-absorbing heat release material.  相似文献   

12.
Carboxyl group-terminated poly(N-isopropylacrylamide) (PNIA-COOH) was synthesized via radical polymerization of N-isopropylacrylamide (NIA) using mercaptoacetic acid (MAA) as a chain transfer agent. The molecular weight of the PNIA-COOH was controlled by changing the molar ratio of MAA to NIA. A water-soluble chitosan derivative, N-(2-hydroxy)propyl-3-trimethylammonium chitosan chloride (HTCC), was also synthesized by reacting chitosan with glycidyltrimethylammonium chloride. Then, chitosan-g-PNIA and HTCC-g-PNIA copolymers were synthesized using the “graft-onto” method by reacting PNIA-COOH with chitosan and HTCC, respectively. The formation of the grafted copolymers was confirmed by Fourier transform infrared spectroscopy, solubility test in water, and scanning electron microscopy — energy dispersive spectroscopy. The thermo-responsive behaviors of the grafted copolymers and the change in lower critical solution temperature (LCST) were also studied. Chitosan-g-PNIA was insoluble in water and behaved like a thermo-responsive hydrogel due to the crosslinking-point action of the chitosan backbone. The swelling ratio of chitosan-g-PNIA increased with increasing PNIA content. HTCC-g-PNIA behaved as a water-soluble thermo-responsive polymer. Compared to the homo PNIA, the LCST of HTCC-g-PNIA was slightly increased.  相似文献   

13.
Poly(n-butyl methacrylate)/poly(methyl methacrylate) polymer networks were synthesized by two-step emulsion polymerization with sodium dodecylsulfonate and polyoxyethylene nonylphenolether as the emulsifier, distilled water as the continuous medium, and potassium persulfate as the initiator. The kinetics of two-step emulsion polymerization was studied. Effects of emulsifier concentration, initiator concentration, and polymerization temperature on monomer conversion and polymerization rate were investigated in detail. Experimental data indicate that both the steady state polymerization rate and monomer conversion increase with the augment of emulsifier concentration, initiator concentration, or reaction temperature.  相似文献   

14.
N,N-diallyl-N,N-dimethylammonium chloride (DADMAC) and vinyl ether of monoethanolamine copolymer (VEMEA) was synthesized by radical polymerization in aqueous media using ammonium persulfate as initiator. Copolymers synthesis was carried out by varying monomer composition at low conversion level. The viscosity of high molecular weight products was measured in aqueous 1 M NaCl solution and it was increased with increasing DADMAC amounts in the copolymer due to increasing positive charge. The structure of the product was identified by FTIR, 1H, 13C-NMR spectroscopies and conductometric titration methods. We calculated monomer reactivity ratios with help of Finemann-Ross, Kelen-Tudos, and inverted Finemann-Ross methods. It was found that DADMAC is more reactive than VEMEA, therefore the amount of DADMAC in the copolymers always dominated regardless of the initial monomer ratio in solution and it was shown that the monomers are connected randomly in the polymer chain. The effect of various parameters such as monomer [M], initiator [I] concentrations, ratio of comonomers, etc. on polymerization was investigated systematically. So, the polymerization rate (Rp) equation was found to be Rp=k[M]2.6[I]0.6 where molar fractions of DADMAC and VEMEA was 90:10 and the temperature was 65 °C. Degree of polymerization was examined by using various monomers and initiator concentrations via the dilatometeric method. It was found that the polymerization rate increased directly with total monomer concentration and initiator content.  相似文献   

15.
The use of vegetable oil macromonomers (VOMMs) as co-monomers in emulsion polymerization enables good film formation without the use of traditional coalescing solvents which constitute volatile organic compounds (VOCs). However, the allylic protons associated with the fatty acid double bonds can result in extensive chain transfer, reduced rates of polymerization, and potential gel content. Different vegetable oils were derivatized to yield their respective VOMMs which were subsequently polymerized into latexes with conventional (meth)acrylate monomers. The degree of ambient crosslinking was related to the extent of chain transfer for the various vegetable oils. The retention of VOMM unsaturation depended on reaction temperature, and the greatest variability between high and low temperatures was exhibited by the linseed oil macromonomer (the highest level of unsaturation). Lower reaction temperatures minimized the negative impact of the chain transfer reactions, yielding latexes with higher molecular weights and greater retention of allylic unsaturation. Core–shell polymers were characterized by bimodal particle size distribution indicating that the presence of VOMM-rich droplets contributed little to homogeneous VOMM distribution. Optimized single-stage polymerizations resulted in significant preservation of unsaturation, good film-forming qualities, rapid drying, and improved solvent resistance. The resulting latexes exhibited potential for use in higher performance application than conventional latexes. This study has demonstrated that drying oils can be incorporated into emulsions in limited quantities as effective reactive monomers for internal plasticization and auto-oxidative crosslinking after application. Broader ranges of incorporation require further study of VOMM reaction kinetics as a function of structure and improved process methods for macromonomer incorporation into emulsion polymers.  相似文献   

16.
Polymer/silicate nanocomposites were prepared via two-step manufacturing process: a master batch preparation and then mixing with matrix polymer. A hybrid of PMMA and Na-MMT with exfoliated structure was first prepared by emulsion polymerization of MMA in the presence of Na-MMT. For the case that SAN24, miscible with PMMA, is used as matrix, we could prepare a nanocomposite with exfoliated structure. However, SAN31 nanocomposite shows the aggregation and/or reordering of the silicate layers due to the immiscibility between SAN31 and PMMA.  相似文献   

17.
Waterborne polyurethane modified by acrylate/nano-ZnO (PUA/ZnO) was synthesized and used to improve the wet rubbing fastness of reactive dyed cotton fabric. The reaction conditions were optimized and the products were characterized by FT-IR, TG, DSC, SEM, and particle size distribution. The dyed cotton fabrics were finished with PUA/ZnO emulsion and the rubbing fastness, ultraviolet resistant property, and wearability of treated fabrics were measured. The wet rubbing fastness of treated fabrics was increased by about 0.5–1 rate to achieve 3–4 rate, and the ultraviolet protection factor (UPF) achieved 50+ level. The whiteness, air permeability, and elongation at break of treated fabric were not decreased significantly. SEM showed that the smooth and reticular coating on the surface of treated fabric reduced the mechanical friction force between dyed fabric and rubbing cloth, and thus improved the rubbing fastness. The decomposition temperature of finished fabric was increased by 50–80 °C.  相似文献   

18.
Polyurethane-poly(2,2,3,3-tetrafluoropropyl acrylate) (PU-PTFPA) triblock copolymer aqueous dispersions were synthesized by three-step polymerization. Infra-red (IR) data verify the copolymerization between PU and TFPA. The properties of copolymer aqueous dispersion and its film cast from the dispersion have been investigated by transmission electron microscopy (TEM), dynamic light scattering (DLS), and some other physical testing methods. TEM observations indicate that the morphologies of copolymer particles formed in water are almost irregular spherical shape with core-shell structure. DLS results verify that the introduction of TFPA monomer changes the average particle size of copolymer particles. The experimental data demonstrate that the factors influencing the properties of PU-PTFPA triblock copolymer aqueous dispersion and its film cast from the dispersion mainly involve PU content, DMPA content and PTFPA content.  相似文献   

19.
Textiles have traditionally been employed over the centuries with great utility in areas as diverse as fashion through to technical textiles. In all these instances the textile itself has been a structural element that once fabricated has limited utility beyond the intended structural and aesthetic application. In recent years there has been a shift towards the incorporation of electronic systems into textile structures. The new paradigm for textiles is the development of systems that not only provide the more traditional aspects of textiles but expands upon this to provide a unique capability to transmit and store information and energy. More importantly these next generation materials will be capable of responding to external stimuli, modifying features of the textile in a direct response to its working environment. A potential route to truly functional electronic textiles is through the application of conducting polymers.  相似文献   

20.
We synthesized a polyhydroxyamide (PHA) copolymer via low-temperature solution polymerization of 3,3'-dihydroxybenzidine with terephthaloyl chloride (80.0 mol%) and isophthaloyl chloride (20.0 mol%) in N,Ndimethylacetamide with the aid of LiCl. We prepared the PHA copolymer derivatives containing the fluorine-based substituents and investigated their solubility, cyclization behavior, and thermal properties using a differential scanning calorimeter (DSC), a thermogravimetric analyzer (TGA), and the simultaneous thermogravimetric analyzer coupled with a mass spectrometer (STA-MS). The chemical structures of the PHA copolymer and its derivatives, as well as the polybenzoxazoles (PBOs) obtained through thermal cyclization of the copolymer and derivatives, were determined by a fourier transform infrared (FT-IR) spectroscopic analysis. The PHA copolymer could be dissolved in organic solvents only with the aid of LiCl, while its derivatives were readily soluble in DMAc and NMP without LiCl at room temperature. The DSC and TGA results demonstrated that the PHA copolymer derivatives could be converted to PBOs at a lower temperature than the PHA copolymer.  相似文献   

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