Cyclohexanone Formaldehyde Resin Research Articles

Synthesis of polymeric emulsifiers based on ketoaldehyde resin and their application in emulsifying styrene/water two‐phase system

AbstractThough the stabilization effect of polymeric emulsifiers onto emulsions is worse than that of small molecular emulsifiers, the application of polymeric emulsifiers can avoid small molecule residues in polymer products. Herein, a series of polymeric emulsifiers (M‐CFR‐x‐K [Na]/M‐MeCFR‐x‐K) are synthesized based on cyclohexanone formaldehyde resin (CFR)/methylcyclohexanone formaldehyde resin (MeCFR), which are firstly modified by maleic anhydride and then neutralized by bases. The effect of different counter ions, terminal groups and chain lengths on emulsion (styrene/water) property is studied by monitoring the stability and droplet size distribution of the emulsions. The results indicate that the emulsifier with KOH as neutralizer has better emulsifying performance than that with NaOH. Besides, the emulsion prepared by M‐MeCFR‐1.20‐K, which has a hydrophilic group just at one end is more stable than that of M‐CFR‐2.25‐K, which both ends are hydrophilic groups. The chain length of polymeric emulsifiers affects the stability of emulsions. And when the acid value is 1.91 mmol/g, the modified resin (M‐CFR‐2.25‐K) has the best emulsifying performance. Furthermore, M‐CFR‐2.25‐K (acid value:1.91 mmol/g) is used for emulsion polymerization. And after the reaction, polystyrene particulates can be directly obtained by precipitation without special demulsification procedure.

Synthesis of Reactive Polyurethane Adhesives and Studying the Effect of Ketonic Resins

In this study, the effects of cyclohexanone formaldehyde ketonic resin (CFR) with different montmorillonite content on the viscosity, initial adhesion strength and temperature resistance of polyurethane one component adhesives were investigated. Cyclohexanone formaldehyde resin (CFR) with varying montmorillonite (MM) content were incorporated into formulation with a specified weight ratio (rate of 10% by weight of polyether polyol.) One-shot technique was used for synthesis. Blank polyurethane was synthesized using polyether polyol and polymeric 4,4'-methylene diphenyl diisocyanate (p-MDI). In experimental studies, the ratio of the isocyanate groups (NCO) to the hydroxyl group (OH) was 4.84. Reaction completion was followed by FTIR spectroscopy. Choloroparaffine was used as a plasticizer to adjust the viscosity and to reduce the fragile structure of the product. The NCO % values of the synthesized adhesive PU were measured by titration. When TGA datas were examined, it was found that the heat resistance of the product increased with the addition of CFR and MM-CFR. As a result, it has been determined that the adhesion properties and thermal resistance were improved with the use of ketonic resins in one component reactive adhesives.

Novel environmentally friendly tannin-cyclohexanone formaldehyde resin for high performance applications

PurposeCyclohexanone-formaldehyde resin (CFR) was in situ modified with tannin (T) in the presence of sodium hydroxide. The purpose of this study is to produce eco-friendly tannin-modified cyclohexanone resins (TCFR) with a one-step method that has higher decomposition temperature than CFR. The solubility, molecular weight and thermal properties of the product were investigated.Design/methodology/approachCyclohexanone, formalin (37 per cent aqueous solution) and tannin were mixed and 20 per cent aqueous NaOH solution was added to produce the resin. Tannin has environmentally friendly bio-based phenolic compounds that the tannin structure has been incorporated into the structure of the cyclohexanone formaldehyde resin during the in situ modification of resin, such as resole resin.FindingsThe improvement of the properties of the TCFRs produced from condensed tannin. TCFRs were soluble in common organic solvents. The product TCFR has a dark red colour.Research limitations/implicationsThe reaction mixture must be stirred continuously. Subsequently, 37 per cent formalin was added drop-wise in total while refluxing. The amount of aqueous NaOH solution of it is limited, as the formed resin may become insoluble in common organic solvents. At the end of the reaction, a water-soluble resin is obtained. Then, the water of water phase was removed from TCFR reaction system, successively by evaporating with rotary evaporator.Practical implicationsThis study provides the application of ketonic resins. The TCFR containing tannin groups may also promote the adhesive strength of a coating.Social implicationsThese resins may be used for the preparation of adhesive. Condensed tannin, with a large amount of Catechol groups was considered for reducing the formaldehyde emission level on the adhesive system.Originality/valueTCFR has been synthesised in the presence of a base catalyst. Environmental and ecological concerns have increased the attention paid by chemical industry to renewable raw materials.

UV‐curing behavior of unsaturated cyclohexanone formaldehyde resins with thiols

ABSTRACTNumerous researches about the modification and application of cyclohexanone formaldehyde resins (CFR) have been conducted, few of them involve in the UV‐curing of unsaturated CFR with thiols. Thus, CFR are synthesized using the rehydrated magnesium‐aluminum hydrotalcite as the catalyst and double bonds are introduced by capping the chain ends with 5‐norbornene‐2,3‐dicarboxylic anhydride. Through monitoring the conversion of double bonds with FTIR, the UV‐curing behavior of unsaturated CFR in the presence of pentaerythritol tetra (3‐mercaptopropionate) is studied. The results show that the conversion of double bonds can reach to 64.1% at 0.66 mW cm−2 of UV light intensity when the molar ratio of double bonds to sulfhydryl groups is 1:1 in the presence of benzoin dimethyl ether (1% of molar amount of double bonds). Considering the similarity between UV‐curing of thiols‐double bonds and thermo‐curing of amine‐epoxy, one diffusion controlled kinetics model is derived and it shows good fitness. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48420.

Synthesis and characterization of new nitrogen‐ and oxygen‐rich cyclohexanone–formaldehyde resin for fast Cd(II) adsorption in aqueous solution

AbstractA new structure of cyclohexanone–formaldehyde resin (CFR) was synthesized via in situ condensation reaction of 2,4,6‐tris(p‐formylphenoxy)‐1,3,5‐triazine (TFPA) with CFR. TFPA was prepared by the reaction of cyanuric chloride and p‐hydroxybenzaldehyde and its structure was confirmed using spectroscopic methods and elemental analysis. The structural, thermal and morphological properties of the nitrogen‐ and oxygen‐rich CFR were studied using Fourier transform infrared spectroscopy, X‐ray diffraction, thermogravimetric analysis and field emission scanning electron microscopy. After characterization, the resin was used as an adsorbent for Cd(II) due to the high level of nitrogen and oxygen in its structure. The effects of various parameters such as pH, concentration and time on the adsorption process were studied. The maximum adsorption capacity of cadmium at pH 8 in 5 min was 83.61 mg L−1. The adsorption isotherm was applied to the Langmuir, Freundlich, Temkin and Dubinin–Radushkevich models. Comparing the correlation coefficient (R2), the Langmuir model was fitted well. Pseudo‐first‐order, pseudo‐second‐order, Elivich and intra‐particle diffusion models of adsorption kinetics were explored. The pseudo‐second‐order model can better explain the adsorption kinetics that shows adsorption being dependent on the number of active sites of the adsorbent. © 2019 Society of Chemical Industry

Polypyrrole–vinyl aniline modified cyclohexanone formaldehyde resin copolymers: a comparative study of the resin preparation

ABSTRACTIn this study, the synthesis of polypyrrole‐b‐vinyl aniline modified cyclohexanone formaldehyde resin (PPy‐b‐CFVAnR) block copolymers by a combination of condensation polymerization and chemical oxidative polymerization processes was examined. First, a cyclohexanone formaldehyde resin containing vinyl aniline units [4‐ vinyl aniline modified cyclşohexanone formaldehyde resin (CFVAnR)] was prepared by a direct condensation reaction of 4‐vinyl aniline and cyclohexanone with formaldehyde in an in situ modification reaction. CFVAnR and pyrrole (Py) were then used with a conventional method of in situ chemical oxidative polymerization. The reactions were carried out with heat‐activated potassium persulfate salt in the presence of p‐toluene sulfonic acid in a dimethyl sulfoxide–water binary solvent system; this led to the formation of desired block copolymers. The effects of the oxidant–monomer molar ratio, dopant existence, addition order of the reactants, and reaction temperature on the yield, conductivity, and morphology of the resulting products were investigated. PPy‐b‐CFVAnR copolymers prepared with a resin‐to‐Py molar ratio of 1:40 showed conductivity in the range 3.7 × 10−1 to 3.8 × 10−2 S/cm. Oxidant‐to‐Py molar ratios of 0.5 and 1.0 were proposed to be the optimum stoichiometries for higher conductivity and yield, respectively, of the copolymer. The morphology of the copolymer (PPy‐b‐CFVAnR) was investigated with environmental scanning electron microscopy analyses. The results indicate that the surface of the copolymer was composed of well‐distributed nanospheres with average particle diameters of 60–85 nm. Also, the synthesized PPy‐b‐CFVAnR had a higher thermal stability than the pure CFVAnR. The chemical composition and structure of the PPy‐b‐CFVAnR copolymers were characterized by Fourier transform infrared spectroscopy and measurement. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 132, 42841.

Novel phenylacetylene based ketonic resins

Purpose – This paper aims to report the synthesis of resins having fluorescence properties, with the help of phenylacetylene (PhAc) by one-step method of in situ modification of ketonic resin. Cyclohexanone-formaldehyde resin (CFR) and acetophenone formaldehyde resin (AFR) were in situ modified with PhAc, in presence of sodium hydroxide (NaOH) by condensation polymerisation. Design/methodology/approach – Ketone, formalin and phenylacetylene were mixed and then 20% aqueous NaOH solution was added to produce the phenylacethylene modified ketonic resin. The solubility, molecular weight and thermal properties of the products were investigated. Findings – These new PhAc-modified ketonic resins (PAc-CFR and PAc-AFR) have fluorescence properties. Research limitations/implications – This study focuses on obtaining a fluorescence resin using a cyclohexanone, acetophenone and PhAc monomer which is an insulator. Practical implications – This study provides technical information for the synthesis of fluorescence comonomers. The modified resins contain acetylene groups. A chemical redox or radical system can be used to polymerise these acetylene groups and resins with much higher molecular weight. The resins may also promote the adhesive strength of a coating and corrosion inhibition to metal surfaces of a coating. Social implications – The resins will be used for the preparation of AB- and ABA-type block copolymers. These block copolymers may exhibit different properties due to incorporation of monomer into the block copolymer structure. Originality/value – PAc-CFR and PAc-AFR have been synthesised in the presence of a basic catalyst. Higher solubility and fluorescence intensity of the modified ketonic resins may increase their applications in the field of electroactive polymers and open new areas. These comonomers have fluorescence property.

Copolymerization of Pyrrole and Thienyl end Capped Cyclohexanone Formaldehyde Resin with Ce(IV) Oxidic Dibenzoate

Block copolymers of polypyrrole (PPy) and thienyl end capped cyclohexanone formaldehyde resin (ThCFR) were synthesized via chemical oxidative polymerization of (Py) and ThCFR in the presence of cerium (IV) oxidic dibenzoate (CODB). The treatment of Py with CODB was maintained in non-aqueous media at room temperature. Several solvents including toluene, dichloromethane (DCM), were used. Besides the role of reaction media, the effect of ceric (IV) oxidic compound on polymerization was investigated. Reactions with constant amount of Py, and CODB to Py mol ratios of 0.33:1.0, 0.5:1.0 and 1.0:1.0 were observed. The results showed that in one-hour limited time, block copolymers could be obtained in toluene and dichloromethane with CODB: Py: ThCFR mol ratio of 1.0: 1.0: 0.01. Conductivities of polypyrroles were determined by 4-point probe technique. Block copolymers were prepared in dichloromethane and toluene, respectively.

New comonomer synthesis from thiophene-2-carbonyl chloride and cyclohexanone formaldehyde resin

Purpose – The purpose of this paper is to synthesise an electro-active monomer containing ketonic resins and then to investigate the redox reaction between Fe+3 and bound thiophene in comonomer. First, thiophene-functionalised ketonic resins were synthesised by esterification reaction of thiophene-2-carbonyl chloride (ThCCl) and hydroxyl groups of cyclohexanone formaldehyde resin (CFR). Thiophene-containing cyclohexanone formaldehyde resin (Th-CFR) was then polymerised by ferric salt. The structures of the specimens were characterised by means of Fourier transform infrared and Proton – Nuclear Magnetic Resonanse (1H-NMR) spectroscopy. Thermal properties of the samples were determined with differential scanning calorimeter. Molecular weights of the specimens were determined by gel permeation chromatography. The obtained samples were also characterised morphologically by scanning electron microscope. Design/methodology/approach – Synthesis of Th-CFR comonomers by a combination of condensation polymerization and chemical oxidation polymerisation processes is described. First, Th-CFR units were prepared by direct condensation reaction of thiophene-2-carbonyl chloride (ThCCl) and hydroxyl groups of CFR. Then, the chemical oxidation (CO) of Th-CFR in the presence of anhydrous iron (III) chloride salt (FeCl3) was performed in chloroform (CHCl3)/acetonitrile mixture solutions at room temperature. Findings – The important structural factor determined quantitatively for Th-CFR is the CFR/ThCCl ratio after reaction. The effect of the mole ratio effect of ThCCl and ketonic resin on the solubility, molecular weight, Tm and Tg values of the comonomers (Th-CFRs) were investigated. Research limitations/implications – The ferric ion (Fe+3) has a standard oxidation potential. Furthermore, FeCl3 can react with thiophene to produce a cation radical. FeCl3 cannot react with hydroxyl groups of ketonic resins. When ferric is used for in situ chemical oxidation application at relatively low temperatures (e.g. < 20°C), the oxidation reactions are usually less aggressive. Practical implications – This work provides technical information for the synthesis of conducting block copolymer and for the synthesis of chain-extended resins. The modified resins contain electro-active monomer as thiophene. The chemical oxidation system has been used to polymerise these thiophene groups and resins with much higher molecular weight might be produced. These resins may also promote the adhesive strength of a coating and corrosion inhibition to metal surfaces of a coating. Social implications – This will be used for the preparation of AB- and ABA-type block copolymers. These block copolymers may exhibit different properties due to incorporation of monomer into the block copolymer structure. Originality/value – Novel Th-CFR comonomers were synthesised. These comonomers have higher glass transition temperature (Tg) and melting temperature (Tm) value than CFR alone. The chemical oxidation system has been used to polymerise these thiophene-functionalised ketonic resins.

Synthesis of cyclohexanone-formaldehyde resin catalyzed by rehydrated Mg–Al hydrotalcite

Abstract Cyclohexanone-formaldehyde resin (CFR) was synthesized over rehydrated Mg–Al hydrotalcite (HT). Therein, Mg–Al HT was rehydrated from Mg–Al HT of good crystallinity using a liquid method. Rehydrated Mg–Al HT (HT-r) shows certain catalytic activity for aldol condensation and catalytic activity is dramatically improved in the presence of hexadecyl trimethyl ammonium bromide (CTAB) because CTAB as a phase transfer catalyst is helpful to enhance the mass transfer among three phases. Both higher temperature and longer reaction time are preferable to increase the molecular weight of CFR. Though the catalytic activity of HT-r decreases as the reutilization cycle increases, the deactivated HT-r can be easily regenerated upon calcining and rehydrating.

Novel comonomer synthesis from thiophene-2-carbonyl chloride and polydimethylsiloxane modified cyclohexanone formaldehyde resin

Purpose – The purpose of this paper is to produce an electroactive monomer containing ketonic resins and then to investigate redox reaction between Fe+3 and bounded thiophene in comonomers. First, thiophene functionalised ketonic resins (Th-CFPDMSR) were synthesised by esterification reaction of thiophene-2-carbonyl chloride (ThCCl) and hydroxyl groups of cyclohexanone formaldehyde resin (CFR). Th-CFPDMSR was then polymerised by ferric salt. Thiophene modified ketonic resins (Th-CFPDMSR) as comonomers were characterised by common techniques such as gel permeation chromatography, proton nuclear magnetic resonance spectroscopy, Fourier transform infrared spectroscopy, differential scanning calorimeter and scanning electron microscope. Design/methodology/approach – Th-CFPDMSR comonomers were synthesised by esterification reaction of ThCCl and hydroxyl groups of ketonic resins. Then, the in-situ chemical oxidation (ISCO) of ThC-CFR in the presence of iron (III) chloride salt (FeCl3) was accomplished in chloroform/acetonitrile mixture solutions at room temperature. Findings – Important structural factor determined quantitatively for Th-CFPDMSR is the CFPDMS/TCCl ratio after reaction. The mole ratio effect of TCCl and ketonic resin on the solubility, molecular weight, melting temperature (Tm) and glass transition temperature (Tg) values of the comonomers (TCCl-CFPDMSR) was investigated. Research limitations/implications – The ferric ion (Fe+3) has a standard oxidation potential. Furthermore, FeCl3 can react with thiophene to produce a cation radical. FeCl3 cannot react with hydroxyl groups of ketonic resins. When ferric is used for ISCO application at relatively low temperatures (e.g. < 20°C), the oxidation reactions are usually less aggressive. Practical implications – This work provides technical information for the synthesis of conducting block copolymer and for the synthesis of chain-extended resins. The modified resins contain thiophene. The chemical oxidation system has been used to polymerise these thiophene groups, and resins with much higher molecular weight might be produced. The resins may also promote the adhesive strength of a coating and corrosion inhibition to metal surfaces of a coating. Originality/value – Novel Th-CFPDMSR comonomers were synthesised. These comonomers have higher Tg and Tm values than CF-PDMSR alone. The chemical oxidation system has been used to polymerise these thiophene functionalised ketonic resins.

Preparation and Characterization of UV-Curable Cyclohexanone-Formaldehyde Resin and Its Cured Film Properties

UV-curable cyclohexanone-formaldehyde (UVCF) resin was prepared with cyclohexanone-formaldehyde (CF) resin, isophorone diisocyanate (IPDI), and pentaerythritol triacrylate (PETA) as base substance, bridging agent, and functional monomer, respectively. The structure of UVCF was characterized by Fourier transform infrared spectroscopy (FT-IR),1H-nuclear magnetic resonance spectroscopy (1H-NMR), and gel permeation chromatography (GPC). The viscosity and photopolymerization behavior of the UV-curable formulations were studied. The thermal stability and mechanical properties of the cured films were also investigated. The results showed that UVCF resin was successfully prepared, the number of average molecular weight was about 2010, and its molecular weight distribution index was 2.8. With the increase of UVCF resin content, the viscosity of the UV-curable formulations increased. After exposure to UV irradiation for 230 s, the photopolymerization conversion of the UV-curable formulations was above 80%. Moreover, when the UVCF content was 60%, the formulations had high photopolymerization rate, and the cured UVCF films showed good thermal stability and mechanical properties.

In situ preparation of cyclohexanone formaldehyde resin/layered silicate nanocomposites

ABSTRACTIn this study, in situ modified cyclohexanone formaldehyde resin (CFR) was prepared from clay (montmorillonite) and polydimethylsiloxane with diamine chain ends [α,ω‐diamine poly(dimethyl siloxane) (DA.PDMS)] in the presence of a base catalyst. Different clay contents (from 0.5 to 3 wt %) were used to produce clay‐modified nanocomposite ketonic resins [layered clay (LC)–CFR] and clay‐ and DA.PDMS‐modified nanocomposite ketonic resins (DA.PDMS–LC–CFR). The polymeric nanocomposite material prepared by this method was directly synthesized in one step. These nanocomposites were confirmed from X‐ray diffraction to have a layered structure with a folded or penetrated CFR, and they were further characterized via Fourier transform infrared spectroscopy–attenuated total reflectance and NMR spectroscopy. The thermal properties of all of the resins were studied with differential scanning calorimetry and thermogravimetric analysis. All of the resins showed higher thermal stability than their precursor CFR resin. The obtained samples were also characterized morphologically by scanning electron microscopy. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2014, 131, 39918.

Preparation of Sulfonated Cyclohexanone-Formaldehyde Resin

Sulfonated cyclohexanone-formaldehyde resin (SCF) was synthesized using cyclohexanone and formaldehyde as raw materials, sodium sulfite as sulfonating agent. The composition of the SCF resin was characterized by FTIR and 13C NMR, and the possible mechanism for formation of the resin was suggested. The effects of reaction parameters, such as ratio of formaldehyde and cyclohexanone, the amount of sulfonating agent, as well as reaction temperature and pH, on the viscosity and average molecular weight were investigated. The results showed that the optimum reaction conditions was that the ratio of reactant was n (formaldehyde):n (cyclohexanone):n (sodium sulfite) = 2.0:1.0:0.7, and pH value of the system was 10 at 90°C temperature. The average molecular weight of the resulted resin was 58392.

Chain extended vinyl aniline modified cyclohexanone formaldehyde resin

PurposeThe purpose of this paper was as follows. The in situ chemical oxidation (ICO) of vinyl aniline modified cyclohexanone formaldehyde resin (CFVAnR) in the presence of potassium persulphate salt (K2S2O8) was accomplished in dimethyl sulphoxide (DMSO) solutions at 35°C and 70°C. The chemical composition and structure of the oxidized CFVAnR were characterised by nuclear magnetic resonance (1H‐NMR) spectroscopy, Fourier transform infrared (FT‐IR) spectroscopy, DSC, TGA and SEM.Design/methodology/approachThe reactive vinyl and amine groups of the cyclohexanone formaldehyde resin were reacted in the presence of potassium persulphate. CFVAn resin was dissolved in DMSO inside a round bottom flask immersed in a water bath thermostated at reaction temperature of 35°C and 70°C, respectively. Solution of K2S2O8 was prepared in DMSO and this was added into the resin solution.FindingsIt was shown that the vinyl groups in the resin were reacted easily with persulphate salt to obtain chain extended CFVAnR (CECFVAnR). The oxidised 4‐vinyl aniline modified cyclohexanone‐formaldehyde resin has solublity in organic solvents.Research limitations/implicationsThe reaction mixture must be stirred continuously. Temperature should be controlled to prevent the thermal polymerisation of vinyl group and higher branching of amino groups. The persulphate ion (S2O82−) has a standard oxidation potential, but when activated by heat (40‐60°C). Furthermore, sulphate radical can react with water or hydroxide to produce hydroxyl radical (−OH). When persulphate is used for in situ chemical oxidation (ISCO) application at relatively low temperatures (e.g. <20°C), the oxidation reactions are usually less aggressive due to a slow generation rate of SO4−.Practical implicationsThis study provides technical information for the synthesis of chain extended resins. The modified resins contain vinyl groups. The chemical radical system has been used to polymerise these vinyl groups and resins with much higher molecular weight might be produced. The resins may also promote the adhesive strength of a coating and corrosion inhibition to metal surfaces of a coating.Social implicationsThis resin will be used for the preparation of AB‐ and ABA‐type block copolymers. These block copolymers may exhibit different properties due to incorporation of ketonic resins into the block copolymer structure.Originality/valueChain extended CFVAnR (CECFVAnR) was synthesised by one step reduction‐oxidation reaction, at 35°C (CECFVAnR1) and 70°C (CECFVAnR2) in the presence of potassium persulphate salt. These soluble resins may overcome difficulties in the applications of polymers and open new application areas. Therefore, the chain extended vinyl aniline modified resin may find a number of new application areas as well as existing UV curable resin and polymer applications.

In situ modification of cyclohexanone formaldehyde resin with boric acid for high‐performance applications

AbstractA boron‐containing cyclohexanone formaldehyde resin (BCFR) was synthesized from cyclohexanone, formaldehyde, and boric acid. The effects of the boric acid concentration, solubility, molecular weight, and thermal properties on the product were investigated. Characterization of the BCFRs was done by NMR spectroscopy, gel permeation chromatography, and Fourier transform infrared–attenuated total reflectance spectroscopy. The thermal properties of the samples were determined with differential scanning calorimetry and thermogravimetric analysis. The study results demonstrate that the resin had higher heat‐resistance properties than the commonly modified cyclohexanone formaldehyde resin. The obtained samples were also characterized morphologically by scanning electron microscopy. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013

Synthesis and Characterization of a New Kind of UV-Curable Cyclohexanone-Formaldehyde Resins

A kind of UV-curable cyclohexanone-formaldehyde resins (UVCF) was prepared by the reaction of cyclohexanone-formaldehyde resin (CFR), isophorone diisocyanate (IPDI) and 2-hydroxyethyl acrylate (HEA). The UVCFIPID-HEA obtained was characterized by fourier transform infrared spectrum (FTIR), nuclear magnetic resonance (NMR). The FTIR and 1H-NMR results show that the terminal acrylate acyloxy was introduced into the structure of the prepolymer. The results of solvent resistance tests show that the solvent resistance property of UVCFIPID-HEA is excellent.

Preparation of a Novel Prepolymer of Polyurethane Acrylate

A new prepolymer of polyurethane acrylate (PUA) was synthesized from cyclohexanone- formaldehyde resin (CFR) with high hydroxyl value, toluene diisocyanate (TDI) and 2-hydroxyethyl methacrylate (HEMA) by using dibutyltion dilaurate as catalyst via two steps. The result from Fourier transform infrared spectrum (FT-IR) showed that methacrylate group was introduced into the terminal of CFR by using TDI as bridge and curable PUA was obtained. Then, the PUA was cured by using azodiisobutyronitrile as catalyst at 110-130°C for 2h. The resulting product has excellent solvent resistance.

Vinyl aniline modified cyclohexanone formaldehyde resins

PurposeThe purpose of this paper is to investigate in situ modification of cyclohexanone‐formaldehyde resins (CFR) by 4‐vinyl aniline (Van). The roles of the reaction temperature, the conductivity, thermal properties, and molecular weight of the product were investigated. CFR was in situ modified with VAn in the presence of sodium hydroxide. Ketonic resin‐bound 4‐vinyl aniline was synthesised with a one‐step method of in situ modification of ketonic resin. The roles of the reaction temperature and the conductivity of the product were investigated.Design/methodology/approachKetone, formalin (37% aqueous solution), vinyl aniline were mixed and then 20% aqueous NaOH solution was added to produce the resin. The solubility, molecular weight and thermal properties of the products were investigated.FindingsThe 4‐vinyl aniline modified cyclohexanone‐formaldehyde resins were found to have conductivity values of 10−4 and 10−2 S/cm and may be considered as conductive ketonic resin. Soluble and processable conductive ketonic resins were developed.Research limitations/implicationsThe reaction mixture of CFR must be stirred continuously at low temperature. Subsequently, 37% formalin was added dropwise in equal portions while refluxing. Temperature should be controlled to prevent the thermal polymerisation of vinyl group and higher branching of amino groups. The amount of vinyl aniline used in reaction mixture is limited since the formed resin may become insoluble in common organic solvents.Practical implicationsThis study provides technical information for the synthesis of conducting resins. The modified resins contain vinyl groups. The chemical redox or radical system can be used to polymerise these vinyl groups and resins with much higher molecular weight may be produced. The resins may also promote the adhesive strength of a coating and corrosion inhibition to metal surfaces of a coating.Originality/valueVinyl aniline modified cyclohexanone formaldehyde resins have been synthesised in the presence of a basice catalyst. These soluble and conductive resins may overcome difficulties in the applications of conducting polymers and open new application areas. Therefore, the vinyl aniline modified resin may find a number of new application areas, as well as existing conducting resin and polymer applications.

Synthesis of cyclohexanone formaldehyde resin‐methylmethacrylate block‐graft copolymers via ATRP

AbstractWell defined block‐graft copolymers of cyclohexanone‐formaldehyde resin (CFR) and methylmethacrylate (MMA) were prepared via atom transfer radical polymerization (ATRP). In the first step, cyclohexanone formaldehyde resin (CFR) containing hydroxyl groups were modified with 2‐bromopropionyl bromide. Resulting multifunctional macroinitiator was used in the ATRP of MMA using copper bromide (CuBr) and N,N,N′,N″,N″‐pentamethyl‐diethylenetriamine (PMDETA) as catalyst system at 90°C. The chemical composition and structure of the copolymers were characterized by nuclear magnetic resonance (1H‐NMR) spectroscopy, Fourier transform infrared (FTIR) spectroscopy, and molecular weight measurement. Molecular weight distributions of the CFR graft copolymers were measured by gel permeation chromatography (GPC). Mn values up to 19,000 associated with narrow molecular weight distributions (polydispersity index (PDI) < 1.6) were obtained with conversions up to 49%. Coating properties of synthesized graft copolymers such as adhesion and gloss values were measured. They exhibited good adhesion properties on Plexiglas substrate. The thermal behaviors of all polymers were conducted using differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012