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Purpose Presently, a wide range of polyurethane adhesives can be obtained using different kinds of polyols and isocyanates. However, the applied temperature of the polyurethane adhesive is not more than 80°C. The film of polyurethane adhesive will be softened and deformed when its applied temperature is more than 100°C. Thus, the mechanical property of the polyurethane adhesive is decreased clearly, which limits its further application. The purpose of the study is to improve the heat resistance of polyols, especially polyester polyols and its resultant polyurethane adhesives.Design/methodology/approach The more rigid benzene ring is introduced into the polyester polyols to improve the heat resistance of its resultant polyurethane adhesive.Findings The more rigid benzene ring has ben introduced into the polyester polyols and the heat resistance of its resultant polyurethane adhesive is improved.Originality/value The polyester polyols with more rigid benzene ring have been prepared successfully by the vacuum melting method when diethylene glycol, neopentyl glycol, 1,6-hexanediol, ethanediol, isophthalic acid, terephthalic acid, sebacic acid and adipic acid are used as raw materials and tetra-isopropyl titanate is adopted as the catalyst. [ABSTRACT FROM AUTHOR]

Purpose At present, the conventional method of preparing cationic fluorinated acrylic latex is to emulsify copolymerised monomers with cationic surfactants. However, there has been a wide concern about using Gemini surfactants to prepare cationic polymer latex to improve its properties. The purpose of this paper was to focus on the synthesis of novel self-crosslinked cationic fluorinated acrylic latex (SCFAL), during which the copolymerised monomers were initiated with a water soluble azo initiator and emulsified with mixed surfactants of Gemini emulsifier and alkyl polyglycoside (APG).Design/methodology/approach The novel SCFAL was prepared successfully by the semi-continuous seeded emulsion polymerisation of butyl acrylate, methyl methacrylate, hexafluorobutyl methacrylate (HFMA) and hydroxy propyl methacrylate (HPMA) in aqueous medium.Findings The conversion is the maximum and the coagulation percentage the minimum when the amounts of emulsifier and initiator are 8 and 0.6 per cent, respectively. The average particle size of the latex is significantly reduced with the increase of the amount of emulsifiers used. However, the average particle size of the latex is increased with the increase of the amount of HPMA. The particle size of the latex is of a unimodal distribution, which means that the particle size was reasonably uniform. Contact angle is increased with the increase of the amount of the HFMA.Practical implications The novel SCFAL can be widely used as significant components in the field of coatings, leather, textile, paper, adhesives and so on.Originality/value SCFAL, which was emulsified with novel mixed surfactants of Gemini surfactant and APG, has been prepared successfully. Influences of amount of initiator, emulsifier, HPMA and HFMA on emulsion polymerisation and/or properties of novel latex are investigated in detail. [ABSTRACT FROM AUTHOR]

The acrylate latex was a kind of production of emulsion polymerization of acrylate or methyl acrylate and other vinyl ester monomers. Starch was a biomaterial which found multiple applications in various branches. Novel approach to acrylate latex manufacture implied usage of composites e.g. the acrylate latex was being doped with starch to improve its properties and create biofriendly, naturally degrading material, and diminishing negative effect of polymeric waste production. In this paper, two methods that acrylate latex modifed with starch are reviewed and summarized. The aim of the review is that provides the reference for use of the starch in modifying the acrylate latex. [ABSTRACT FROM AUTHOR]

The novel cationic polyacrylate latex containing fluorine silicon was successfully prepared via soap-free emulsion polymerization of butyl acrylate, methyl methacrylate, vinyltriethoxysilane and hexafluorobutylmethacrylate in water phase, which were initiated with water soluble azo initiator and emulsified with the mixed surfactants polymerizable emulsifier and OP-10. The films of the resultant latex were characterized by Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and contact angle (CA) determinator, respectively. In comparison with the conventional polyacrylate latex, the thermal stability and water resistance of novel latex film are improved. The conditions of preparing the novel cationic acrylate latexes were optimized. The optimum conditions of preparing the novel latex are as follows: the amount of emulsifiers and the initiator are 6.0% and0.3%, respectively; both the amount of VETS and amount of HFMA are 6.0%. In this case, the conversion is high and the polymerization stability is good. [ABSTRACT FROM PUBLISHER]

The novel cross-linking (butyl acrylate- co-isobornyl methacrylate) colloids are prepared via semi-continuous seeded emulsion polymerization of butyl acrylate, isobornyl methacrylate and N-methylol acrylamide in aqueous phase using mixture of polyethylene glycol mono(octylphenyl) ether and sodium dodecyl sulphate as emulsifier and potassium persulphate as initiator. The optimal composition for preparing the novel cross-linking colloid was determined, and the structure of the as-prepared colloid was confirmed with FTIR spectrum. The formation of colloidal polymer was also corroborated by a difference between glass transition temperatures of colloid film and corresponding homopolymers. Calorimetry measurements showed that the colloid is composed of random copolymer. The particle size distribution exhibits unimodal character, suggesting a high stability of the colloid polymer. [ABSTRACT FROM AUTHOR]

Nonylphenol ethoxylates (NPEOs) are widely used as surfactants for emulsion polymerization and for post adding stabilization for latex applications in formulations with high filler content. However, NPEOs are bioaccumulative and persistent in the environment while nonylphenol, the breakdown product of NPEs, is an endrocrine disruptor. Therefore, it has been recommended to ban technical processes using NPEOs as surfactants. The acrylic polymer latex was prepared via semi-continuous seeded emulsion polymerization of butyl acrylate and methyl methacrylate in water phase initiated with potassium persulfate when nonylphenol ethoxylates are replaced with alkyl polyglycoside (APG) surfactants. The structure of the resultant acrylic polymer latex is confirmed with Fourier transform infrared spectroscopy spectrum. Differential scanning calorimetry confirms that the resultant latex is a kind of random copolymer and the consistency among the chain segment is fairly good. Influences of amount of APG on the properties of the resultant latex and its film were investigated. Results show that the particle size of the latex is decreased with the increase of the amount of APG. And the ionic stability of latex is also improved with the increase of the amount of APG. However, the water-resistance of the film of the latex is decreased with the increase of the amount of APG. [ABSTRACT FROM AUTHOR]

BA-MMA-POMA copolymer latex was successfully prepared by soap-free emulsion polymerization of 2-(perfluoro-(1,1-bisisopropyl)-2-propenyl)oxyethyl methacrylate(POMA) with butyl acrylate(BA), methyl methacrylate (MMA) initiated by K [ABSTRACT FROM AUTHOR]

The acrylate emulsion was prepared via pre-emulsified and semicontinuous seeded emulsion polymerization technology when nonreactive emulsifiers such as sodium dodecyl-benzenesulfonate (DSB) are replaced with reactive emulsifiers such as sodium2-hydroxy-3-(methacryloyloxy)propane-1-sulfonate (HPMAS). Influence of HPMAS on the particle size, water resistance, viscosity, rheology, and stability of the emulsion was studied. Results show that the particle size and the viscosity of the emulsion are increased with the added amount of HPMAS. However, water resistance of film first is increased and then decreased with the increase of the added amount of HPMAS. The water resistance of the film is best when the added amount of HPMAS is 2.0%. The viscosity of the emulsion is increased with the increase of the added amount of HPMAS. Both the mechanical stability and the freezing-thaw stability of the emulsion are improved when DSB is replaced with HPMAS during the course of the emulsion polymerization. The emulsion is of rheological properties of pseudo-plastic fluid and belongs to non-Newtonian fluid. [ABSTRACT FROM AUTHOR]

Abstract: The novel fluorinated acrylate resin was successfully prepared by solution polymerization of 2-(perfluoro-(1,1-bis-isopropyl)-2-propenyl)oxyethyl methacrylate (POMA) with butyl acrylate (BA), methyl methacrylate (MMA) and methacrylic acid (MAA) initiated by AIBN in the co-solvents of ethyl acetate, butyl alcohol and toluene. POMA was synthesized from the intermediate perfluoro nonene and 2-hydroxyethyl methacrylate as the staring reactants. Films of the novel fluorinated acrylate resin were prepared by coating the resin directly on the clean glass sheet and allowed to dry at room temperature. The characteristics of the film such as hydrophobicity, glass transition temperature and thermal stability were characterized with the contact angle, differential scanning calorimetry and thermo-gravimetric analysis respectively. The structure of the novel fluorinated acrylate resin was investigated by Fourier transform infrared (FTIR) spectrometry. The influences of the fluorine content on the performance of the acrylate resin were studied. Results show that the hydrophobicity, chemical resistance, glass transition temperature and thermal stability of the acrylate resin are improved when the fluorinated monomer is introduced to copolymerize with other monomers. However, the hydrophobicity of the fluorinated acrylate resin is improved slightly via annealing. [Copyright &y& Elsevier]

The nano-SiO2/acrylic composite emulsion with the structure of interpenetrating networks was prepared by introducing nano SiO2 particles formed in situ with the hydrolyzation of traethylorthosilicate in the soap-free emulsion polymerization of acrylate. The structures, morphologies, particle size, thermal and mechanical properties of composite emulsion were characterized with FTIR, TEM, particle size analyzer, thermal analyzer, and tensile-testing machine. Influence of reactive emulsifier on the water resistance, particle size and its distribution of composite emulsion was studied. And influence of different added amount of tetraethyl orthosilicate (TEOS) on the thermal and mechanical properties of composite emulsion was investigated. Results show that water resistance of composite emulsion is increased in comparison with the emulsion prepared with the conventional emulsion polymerization and the average particle size is small and its distribution is good. SiO2 inorganic network acts as the crosslinked point in the acrylic polymer network, and covalently linked with organic phase. Thermal stability and pendulum hardness of composite emulsion are strengthened with the increase of the added amount of TEOS. However, tensile strength and broken elongation of film first is increased and then decreased with the increase of the added amount of TEOS. The tensile strength and broken elongation of film reach its maximum value when the added amount of TEOS is 4.5% and 3.0%, respectively. [ABSTRACT FROM AUTHOR]