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1.
At present, most negative working lithographic plates use organic solvents as a developing medium. These developers have the obvious disadvantages of toxicity, fire risk, and are more expensive than the aqueous developers. This work describes the synthesis and characterization of materials that have similar photoactive properties to existing materials, but are soluble in water or aqueous medium rather than organic solvents. These materials are terpolymers comprising of one sort of material to induce water solubility, such as methacrylic acid (MAA) and another material to give the photoactive response such as glycidyl methacrylate (GMA). The tertiary‐butyl‐4‐vinyl phenyl carbonate (t‐BOCVP) was added as a chemically amplifying agent. Various terpolymers were prepared via free‐radical solution polymerization, typically in methyl ethyl ketone (MEK). Crosslinking reaction was induced using mixed arylsulphonium hexafluoroantimonate (MAS+ ‐SbF) as a photogenerating acid. It was found that the films of the terpolymer containing 85 mol % of GMA unit with the addition of 5 mol % rather than 2 mol % of the t‐BOCVP in the feed ratio gave good acid resistance and good adhesion to the surface of the zinc plate. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   

2.
A water‐developable negative photoresist based on the photocrosslinking of N‐phenylamide groups was prepared by the copolymerization of 4‐styrenesulfonic acid sodium salts (SSS) with N‐phenylmethacrylamide (copolymer A) or p‐hydroxy‐N‐phenylmethacrylamide (copolymer B), and its properties such as solubility changes, photochemical reaction, and photoresist characteristics were studied. The copolymer containing a relatively higher amount of SSS units was soluble in water. Solubility changes of the copolymers in the various buffer solutions of pH 4 ~ 11 and in water upon irradiation were observed by the measurement of insoluble fraction. The copolymers were soluble in water before irradiation, whereas they became insoluble upon irradiation with the UV light of 254 nm. The photochemical reaction of the copolymer studied by the UV and IR absorption spectroscopies indicated that a photo‐Fries rearrangement was favored for copolymer A, whereas a photocrosslinking reaction was predominate for copolymer B. Resist properties of the copolymers were studied by measurement of the normalized thickness and by development of the micropattern. Negative tone images with a resolution of 1 μm were obtained with these materials that have a sensitivity (D) of ~ 1100 mJ/cm2 with an aqueous developing process.© 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 1172–1180, 2002  相似文献   

3.
Syntheses of the copolymers of methyl methacrylate and methacrylic acid were carried out by free radical chain polymerization in the presence of benzoyl peroxide (BPO) as an initiator. The effects of the monomer ratio and polymerization time on the averaged molecular weights, polydispersity index, and glass transition temperature were investigated. FTIR and NMR were used for functional group characterization, GPC for average molecular weights and the distribution, elemental analysis for CHO content, and DSC for the glass transition temperature. The copolymers were mixed with tripropylene glycol diacrylate (TPGDA) and trimethylol propane ethoxylated triacrylate (TMPEOTA), 2‐hydroxy‐2‐methyl‐1‐phenyl‐propan‐1‐one (Darocur® 1173) and benzophenone (Darocur® BP) with anthraquinone for visibility of images. The photosensitive coating was spin‐coated onto the anodized aluminum plate on which a thin film was formed. The wet film was then coated with PVA solution as an oxygen barrier layer. The plate assembled with a control wedge and a black color separation film was exposed to UV radiation at different exposure times. The plate was developed in a dilute alkaline developer. The resulting plate was evaluated for its reproduction properties in terms of surface properties (hydrophilic/hydrophobicity) by contact angle measurement of image/nonimage areas, resolution by microline, tone reproduction, and adhesion tests. The article describes the results of the syntheses, characterizations, and uses of the copolymer as a binder of a negative, lithographic printing plate. The present lithographic printing plate is good for a medium viscosity printing ink to produce medium printing quality on uncoated paper. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 1829–1837, 2002  相似文献   

4.
Novel (meth)acrylate tetrapolymers based on 2-hydroxyethyl methacrylate (HEMA) were synthesized via free-radical polymerization in refluxing xylene under monomer-starved conditions for use in negative photoresist formulations. 2,2′-Azobis(2-methylbutyronitrile) was used as initiator and 2-mercaptoethanol as chain transfer agent. Optimized resist formulations were obtained with a relatively narrow polydispersed (D=1.86) low molecular weight copolymer (Mn=1677) of 2-hydroxyethyl methacrylate (HEMA), isobornyl methacrylate (IBMA), cyclohexyl methacrylate (CHMA) and acrylic acid (AA), in a 40/30/23/7 weight ratio. A novel high-resolution single layer negative tone photoresist suitable for 193 nm and e-beam lithography that meets basic performance requirements (aqueous-base development, enhanced etch resistance, sub-0.2 μm resolution) was developed from the aforementioned (meth)acrylate tetrapolymer, the poly(2-hydroxyethyl methacrylate-co-cyclohexyl methacrylate-co-isobornyl methacrylate-co-acrylic acid) (PHECIMA) and a sulfonium salt photo acid generator. The key-components for the negative image formation (photoacid induced crosslinking) are the hydroxyl groups of the HEMA moieties. The swelling-free negative resist material was developed in diluted aqueous base [tetramethyl ammonium hydroxide, (TMAH) 0.26×10−2N] and presented enhanced etch resistance without the use of etch resistance promoters. 0.20-0.14 μm lines were obtained upon 193 nm and/or e-beam lithography.  相似文献   

5.
A kind of polyacrylamide (PAM) latex product dispersed in an aqueous solution was successfully prepared through the aqueous two‐phase polymerization of acrylamide in an aqueous solution of poly(ethylene glycol) (PEG). The effects of various polymerization parameters on the size and morphology of droplets rich in PAM were systematically investigated. The droplet size and morphology was significantly influenced by the polymerization rate. The high polymerization rate caused the formation of stripe‐shaped droplets because of the aggregation of more droplets rapidly separated from the continuous phase. At the same time, the monomer partition behavior mainly relied on the temperature, and the PEG concentration also dramatically affected the droplet size and morphology. The increase in PEG concentration not only changed the monomer partition behavior and restrained droplet aggregation but also shortened the critical PAM radical chain length and accelerated the droplet formation. Furthermore, the stirring speed was also recognized as the correlative factor that affected the droplet stability and monomer diffusion rate from the continuous phase into the droplets. The addition of salt and alcohol altered the droplet stability and the final droplet size and morphology. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   

6.
Commercial light‐sensitive resins for Rapid Prototyping of cellular materials are often unsuitable for different molding techniques because removal of the mold uses thermal decomposition at temperatures of up to 600°C. In this study, a resin formulation based on water‐soluble polymers was developed and evaluated regarding its usability as sacrificial mold material. The base monomer dimethylacrylamide gave fast curing and excellent polymer solubility. Methacrylic acid was found to be a useful comonomer to improve mechanical strength and feature resolution. The latter criterion was also improved by adding poly(vinyl pyrrolidone) as filler and by using a hydrolytically cleavable crosslinking agent such as methacrylic acid anhydride. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 2286–2298, 2005  相似文献   

7.
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  相似文献   

8.
The photodegradation of poly(vinyl alcohol) (PVA) in aqueous solution was investigated under UV exposure and pulsed‐laser irradiation. The degradation under UV exposure was studied at different pH values and with the addition of potassium chloride and potassium dichromate. The pulsed‐laser degradation of PVA was investigated with a Nd : YAG laser, operating at a wavelength of 266 nm with about 6‐ns pulses. The pulsed‐laser degradation was studied at different polymer concentrations and light intensities. Samples were analyzed by gel permeation chromatography. The degradation rate coefficients were determined by the application of a continuous distribution model. The photodegradation rates under UV exposure were highest at extremes of pH and were greatly enhanced by the addition of potassium chloride and potassium dichromate. The pulsed‐laser degradation of the polymer decreased with increasing polymer concentration, although a threshold light intensity was required to initiate the degradation process. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 958–966, 2006  相似文献   

9.
BACKGROUND: Newly synthesized composite films of P(glycidyl methacrylate85co‐vinylferrocene15)/Poly(glutaraldehyde)/ Polypyrrole [P(GMA85co‐VFc15)/PGA/PPy] and Poly(3‐methylthienyl methacrylate85co‐vinylferrocene15)/Polypyrrole [P (MTM85co‐VFc15)/PPy] were used as matrices for tyrosinase based working electrodes. Direct covalent attachment of enzyme was carried out via the pendant epoxy groups of P(GMA85co‐VFc15) film, and the entrapment of enzyme was achieved for electrode containing P(MTM85co‐VFc15) film via electropolymerization of pyrrole in the presence of enzyme. The aim of the study is amperometric determination of various phenolics and investigation of the effect of interfacial interactions between enzyme and matrices on biosensor response. RESULTS: The lowest detection limit and the highest sensitivity for a P(GMA85co‐VFc15) based working electrode was found to be 0.113 µmol L?1 for 4‐methoxyphenol, 40 nA (µmol L?1)?1 for pyrocatechol, respectively. Results showed that sensitivities were at least 8500–55000 times higher than the results in previous P(GMA‐co‐VFc) related studies. CONCLUSION: Facilitated electron transfer was achieved by means of mediator incorporated in conductive composites of VFc based redox copolymers. The effect was greater when enzyme was covalently bonded via epoxy groups due to the proximity of enzyme, mediator and electrode surface. Results showed that a multifunctional surface was provided on electrodes since the suggested copolymers could mediate an electrochemical reaction, and the multifunctional surface was capable of coating with conductive PPy. Copyright © 2011 Society of Chemical Industry  相似文献   

10.
High‐solids, low‐viscosity, stable polyacrylamide (PAM) aqueous dispersions were prepared by dispersion polymerization of acrylamide in aqueous solution of ammonium sulfate (AS) using poly (sodium acrylic acid) (PAANa) as the stabilizer, ammonium persulfate (APS) or 2,2′‐Azobis (N,N′‐dimethyleneisobutyramidine) dihydrochloride (VA‐044) as the initiator. The molecular weight of the formed PAM, ranged from 710, 000 g/mol to 4,330,000 g/mol, was controlled by the addition of sodium formate as a conventional chain‐transfer agent. The progress of a typical AM dispersion polymerization was monitored with aqueous size exclusion chromatography. The influences of the AS concentration, the poly(sodium acrylic acid) concentration, the initiator type and concentration, the chain‐transfer agent concentration and temperature on the monomer conversion, the dispersion viscosity, the PAM molecular weight and distribution, the particle size and morphology were systematically investigated. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   

11.
The thermoresponsive properties in aqueous solution of the graft copolymer poly(acrylic acid‐co‐2‐acrylamido‐2‐methyl propane sulfonic acid)‐g‐poly(N‐isopropylacrylamide) [P(AA‐co‐AMPSA)‐g‐PNIPAM] were studied and compared to the corresponding behavior of the poly(acrylic acid)‐g‐poly(N‐isopropylacrylamide) (PAA‐g‐PNIPAM) graft product. Both products contain about 40% (w/w) of PNIPAM, whereas the backbone, P(AA‐co‐AMPSA), of the first copolymer contains about 40% of AMPSA mole units. The strongly charged P(AA‐co‐AMPSA)‐g‐PNIPAM graft copolymer was water soluble over the whole pH range, whereas the PAA‐g‐PNIPAM copolymer precipitated out from water at pH < 4. As a result, the first product exhibited a temperature‐sensitive behavior in a wide pH range, extended in the acidic region, whereas in semidilute aqueous solutions, an important thermothickening behavior was observed, even at low pH (pH = 3.0). © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 3466–3470, 2004  相似文献   

12.
The cationic–nonionic dispersing centers with different chain lengths of poly ethylene glycol methyl ether (N‐PDEA 750, N‐PDEA 2000) were prepared from N‐diethanol amine (NDEA), isophorone diisocyanate (IPDI), and poly(ethylene glycol methyl ether) (PEO Mw = 750 and 2000), whereas aqueous cationic–nonionic polyurethane (N‐PDEA PU) with different side chain lengths were prepared by N‐PDEA 750 (or N‐PDEA 2000), 4,4‐methylene bis(isocyantocyclohexane) (H12MDI), polytetramethylene glycol (PTMG 2000), ethylene diamine (EDA), and glycolic acid (GA) as cationic–nonionic dispersing center, hard segment, soft segment, chain extender, and quarternizing agent, respectively. The thermal and mechanical properties of PU casting film were then discussed. We also used N‐methyldiethyolamine (N‐MDEA) without PEO as cationic dispersing center to synthesize aqueous cationic PU (N‐MDEA PU). The PU blends were blending N‐PDEA 750 PU and N‐MDEA PU by different weight ratios and the physical properties of casting films and coated fabric of PU and PU blends were investigated. Regarding the thermal properties, we have found out that the cationic–nonionic PU (N‐PDEA 750 PU, N‐PDEA 2000 PU) has lower Tgs, Tms, TmH, and ΔHH than N‐MDEA PU, apart from ΔHs. The N‐PDEA 2000 PU with longer side‐chain PEO has lower Tgs, higher Tms and ΔHs than N‐PDEA 750 PU. As for mechanical property, N‐PDEA PU has lower tensile strength of casting film compared with N‐MDEA PU. Regarding the comparison of side chain length of PEO, N‐PDEA 2000 PU with longer side chain has higher tensile strength than N‐PDEA 750 PU with shorter side chain length. In addition, N‐PDEA 2000 PU group that shows hard property in stress–strain curve, whereas N‐PDEA 750 PU shows soft property. The tensile strength of PU blends decreases as the content of N‐PDEA 750 PU increases. When the low‐blend ratio of N‐PDEA 750 PU (e.g., 5%), the tensile strength of casting film only shows less influence that can improve the elongation effectively. In terms of coating‐treated fabrics, cationic–nonionic PU‐coated fabrics show lower waterproof capacity (WP) than those treated by cationic PU. However, the water vapor permeability (WVP) and antiyellowing of the N‐PDEA 750 PU coated fabrics are significantly better than the one treated by cationic polyurethane. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 2963–2974, 2006  相似文献   

13.
A cationic moiety, N‐(3‐chloro‐2‐hydroxypropyl)trimethyl ammonium chloride (CHPTAC), was incorporated onto chitosan in an aqueous alkaline solution. Thus, modified chitosan was prepared. A series of modified chitosans with different molecular weights and charge densities were synthesized through the alteration of the molar ratio of CHPTAC to chitosan in the reaction mixture. The synthesized modified chitosans were thereafter characterized by a variety of physicochemical characterization techniques to confirm that modification did take place. Furthermore, the feasibility of applying modified chitosans as flocculants was assessed, and they were compared with the native chitosan in model colloidal suspensions of kaolin and iron‐ore powder. The results indicated that the unmodified chitosan itself was a good flocculating agent. The flocculation performance of the chitosan could be altered by the incorporation of the CHPTAC moiety. Studies showed that not all the modified chitosans had superior flocculation performance versus the native chitosan. Among the different grades, the modified chitosan with a moderate molecular weight and a moderate charge density showed the best flocculation performance in both model suspensions. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   

14.
The interaction of hydrophobically modified (HM) polybetaines with selected small molecule surfactants in aqueous solution was investigated using rheological and surface tension analyses. The polymers included acrylamide‐based, HM polybetaines containing N‐butylphenylacrylamide (BPAM) and specified amounts of sulfobetaine, 3‐(2‐acrylamido‐2‐methylpropanedimethylammonio)‐1‐propanesulfonate (AMPDAPS), or carboxybetaine, 4‐(2‐acrylamido‐2‐methylpropyldimethylammonio)butanoate (AMPDAB); corresponding control (co)polymers lacking BPAM and/or betaine comonomer(s) were also examined for comparative purposes. Low charge density terpolymers exhibited greater viscosity enhancement with the addition of surfactant compared to the high charge density terpolymers. The addition of sodium dodecyl sulfate (SDS) produced the largest increase in solution viscosity, while N‐dodecyl‐N,N,N‐trimethylammonium bromide (DTAB), N‐dodecyl‐N,N‐dimethylammonio‐1‐propanesulfonate (SB3–12), and Triton X‐100 enhanced polymer solution viscosity to a lesser degree. In most cases, the high charge density carboxybetaine terpolymer exhibited diminished solution viscosity upon surfactant addition. The polymers lacking hydrophobic modification showed no detectable viscosity enhancement in the presence of surfactants. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 658–671, 2004  相似文献   

15.
Dispersion copolymerization of acrylamide with acrylic acid in an aqueous solution of ammonium sulfate using poly(2‐acrylamido‐2‐methylpropanesulfonic acid sodium) as the stabilizer and ammonium persulfate (APS) as the initiator was investigated. The influence of initiator concentration, stabilizer concentration, ammonium sulfate concentration, chain‐transfer agent concentration, and polymerization temperature on the copolymerization was discussed. The results showed that varying the ammonium sulfate concentration could affect the particle size and the intrinsic viscosity of the copolymer significantly. With increasing the stabilizer concentration, the particle size of the copolymer decreased first, and then increased, meanwhile the intrinsic viscosity of the copolymer decreased. The increase of initiator concentration, chain‐transfer agent concentration, and polymerization temperature resulted in the increase in the particle size. Polydisperse spherical particles were formed in the system, and the kinetics for the dispersion copolymerization were discussed. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 3685–3690, 2006  相似文献   

16.
More accurate signal assignment for 1H‐ and 13C‐NMR spectra of aqueous solutions of polyamideamine‐epichlorohydrin (PAE) resin and its related compounds was achieved by using distortionless enhancement of polarization transfer (DEPT) and C‐H correlation spectroscopy (COSY) methods. On the basis of the assignment, we developed new methods to determine the content of four‐membered azetidinium ring (AZR) and number‐average degree of polymerization (DPn) of the repeating unit of PAE by using NMR. Degree of introduction of epichlorohydrin into polyamideamine chains at the initial stage was 75–80%, and the resultant AZR content per one repeating unit in the PAE sample prepared in this study was about 72%. DPn of the initial polyamideamine was 32, and this value decreased to about 18 during the PAE preparation process. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 1847–1854, 2004  相似文献   

17.
Connection reliability between Large Scale Integrated circuit (LSI) and electronic devices is increasingly important with the miniaturization of electronic devices. For the formation of fine conductors on wiring in electronic devices, copper electroplating is generally applied and is controlled with various organic additives. In this study, for the purpose of developing additives capable of working on a finer conductive copper circuit, we focused our attention on the synthesis of organic additives with inhibition action for the plating. Generally, poly(ethylene glycol) (PEG) was used as an inhibitor. We synthesized the PEG derivatives, which were α‐(2‐chloroethyl)‐ω‐chloropoly(oxyethylene) (PEG‐Cl) and α‐(2‐sulfoethyl)‐ω‐sulfopoly(oxyethylene)disodium, and evaluated them for their Via‐filling properties. Good filling properties were achieved by the addition of these synthesized materials to a normal copper‐plating bath. Furthermore, with PEG‐Cl, good filling properties were achieved without chlorine ions, which were usually added to the bath. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 837–840, 2005  相似文献   

18.
An epoxy resin (NPES‐904, epoxy equivalent weight is 815) with a repeating unit, n > 4 was selected as a polymer backbone of polymeric dye. Water‐reducible epoxy resin was prepared by a semiesterification of its secondary hydroxy group with succinic anhydride and then dispersed to aqueous phase after it was neutralized with triethylamine. An aqueous polymeric dye was obtained from a ring opening reaction of that epoxy resin with amino group of a direct dye (soluble dye such as C. I. Acid Blue 62, C. I. Direct Orange 39 or C. I. Direct Red 2). These aqueous polymeric dye dispersions carried the average particle sizes between 50 and 90 nm. A polyaziridine was added as a latent curing agent and forming a self‐curable system of aqueous polymeric dye solution, which was stable in aqueous phase when its pH remained above 8.0. This aqueous polymeric dye was self‐cured on drying at ambient temperature and results in the formation of waterproof and solvent‐resistant polymeric dye. These self‐curable polymeric dyes had potential for jet ink printing and dyeing applications. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 1919–1931, 2006  相似文献   

19.
Polyesters based on poly(alkyl anhydride), aromatic anhydrides, and polyglycols were synthesized by thermal and catalytic condensation polymerization techniques. The polymerization conditions were optimized by the variation of the monomer concentration, reaction temperature, and so on to achieve the desired properties. The reaction was monitored by the measurement of the acid values at different stages of the polymerization reaction. The water solubility of these polyesters was achieved by the termination of the reaction with the addition of ammonia. These polyester resins were characterized with IR and viscosity measurements. The electrical properties of polyester resins coated and cured on glass cloth were measured with the idea of using them as impregnating varnishes. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007  相似文献   

20.
The extensional viscosity for aqueous solutions of high molecular weight poly(acrylamide) copolymers and poly(ethylene oxide) homopolymers was measured using a laboratory‐designed screen extensional rheometer. A Bingham model was developed to estimate the average local polymer coil extensional viscosity (ηcoil). A strong correlation was found between the measured ηcoil values and the polymer extensional viscosity predicted by a bead‐spring model. The dilute aqueous solution drag reduction was measured with a rotating disk instrument under conditions minimizing the effects of shear degradation. Extensional viscosity and drag reduction measurements were performed in deionized water and in 0.514M sodium chloride. The relative drag reduction efficiency values (Δ) in both solvents were found to strongly correlate with measured ηcoil values. This is the first report of the accurate prediction of drag reduction behavior for a wide range of polymer types in various solvents from the independently measured molecular parameters ηcoil and [η]C. The often‐used relative drag reduction efficiency expressed as the product of [η]C and Δ can now be replaced by the absolute drag reduction efficiency [η]Cηcoil. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 1222–1231, 2001  相似文献   

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