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Motivated by the globally increasing concern over environmental protection, the interest of a large part of the scientific community focuses on the development of green surfactants aiming to replace traditional toxic surfactants-based alternatives. The purpose of this paper is to prepare acrylate copolymer latex modified with fluorine and silicone monomer, which is emulsified with the green surfactants of sodium rosinate and alkyl polyglycoside (APG).

A series of acrylic copolymer latexes containing fluorine–silicon have been prepared by semi-continuous seed emulsion polymerisation of mixed monomers of methyl methacrylate (MMA), butyl acrylate (BA), hexafluorobutylmethacrylate (HFMA) and vinyltriethoxysilane (VTES) and emulsified by green mixed surfactants of sodium rosinate and APG.

The optimum recipe of preparing the emulsion is as follows: the amount of emulsifiers is 6 per cent and the mass ratio of sodium rosinate to APG is 1:3. The amount of initiator is 0.4 per cent, and the amounts of the silicon monomer and fluorine monomer are 5 and 7 per cent, respectively. In comparison with the acrylate latex prepared without fluorine monomer and silicon monomer, the thermal stability and the water resistance of the film of the resultant latex clearly improved.

The acrylic copolymer latexes containing fluorine–silicon emulsified with green surfactants can be used in the coatings, adhesives, finishing agents and so on.

The acrylic copolymer latexes containing fluorine–silicon have been prepared by semi-continuous seed emulsion polymerisation. The green mixed surfactants of sodium rosinate and APG have been used as the emulsifiers to replace traditional toxic surfactants-based alternatives.

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).

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.

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.

The novel SCFAL can be widely used as significant components in the field of coatings, leather, textile, paper, adhesives and so on.

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.

The purpose of this research is to prepare a dispersion resin with good dispersity and a colour paste with good stability. At present, the colour paste is being prepared using the pigment dispersion resin which has the group quaternary ammonium. The dispersion resin prepared has good dispersity of pigment and extender. However, the stability of storage and construction of the colour paste is relatively poor, which has a negative influence on the application of cathodic electrodeposited (CED) coatings. However, the detailed investigation on the dispersion resin and the stable colour paste has not been reported.

Three steps are adopted to prepare the dispersion resin, that is blocking toluene diisocyanate (TDI), quaternary ammoniation of blocked TDI and ring opening of epoxy resin. The resultant dispersion is used to prepare the colour paste. The factors, which have an influence on the dispersity of the dispersion resin and stability of the colour paste, are optimised.

The typical recipes of preparing the dispersion resin and the resultant colour paste are obtained. The dispersity of the dispersion resin and stability of the colour paste are good based on the typical recipe. In addition, the film of the CED coating is smooth, dense and hard when the colour paste is used in the CED coating.

The dispersion resin can be used to prepare a colour paste, which can be used in the CED coatings. In addition, it also can be applied as a binder of coatings and adhesions.

The factors, which have an influence on the dispersity of the dispersion resin and stability of the colour paste, are studied in detail. The typical recipes of preparing the dispersion resin and the resultant colour paste are obtained. Based on the typical recipe, the dispersity of the dispersion resin and stability of the colour paste are good.

The purpose of this research was to synthesize a novel cross-linked latex copolymerised by butyl acrylate (BA), isobornyl methacrylate (IBOMA), hydroxy propyl methacrylate (HPMA) and dodecafluoroheptyl methacrylate (DFMA). IBOMA is a very useful functional monomer. Its molecular structure not only contains bornyl acetate alkoxy but also includes a double bond, which can be copolymerised with other unsaturated monomers via free radical polymerization. The large nonpolar bicyclic alkyl in bornyl acetate alkoxy offers the polymer chain strong space steric protection, which endows the polymer with some special properties.

The semi-continuous seeded emulsion polymerisation technology was adopted to copolymerise BA, IBOMA, HPMA and DFMA in the water phase, which was initiated with potassium persulfate (KPS) and emulsified with the mixed surfactants of sodium dodecyl sulphate (SDS) and OP-10.

The particle size of the latex decreases with an increase in the amount of IBOMA. All the latexes have good mechanical stability and calcium ion stability. The latex has good film-forming property when the IBOMA amount is controlled moderately. The optimal IBOMA amount is 10.00 g. The thermal stability and water resistance of the film are improved.

The latexes can be applied as a binder of coatings and adhesions.

The effect of the amount of IBOMA and BA on the properties of the resultant latex and its film were investigated in detail. In comparison with the latexes copolymerised without IBOMA, the novel latex has better thermal stability and water resistance.

A transmission tower usually experiences bolt loosening under long-term alternating cyclic load, which may lead to collapse of the tower in extreme operating conditions. The paper aims to propose a data-driven identification method for bolt looseness of complicated tower structures based on reduced-order models and numerical simulations to perceive and evaluate the health state of a tower in operation.

The equivalent stiffnesses of three types of bolt joints under various loosening scenarios are numerically determined by three-dimensional finite element (FE) simulations. The order of the FE model of a tower structure with bolt loosening is reduced by means of the component modal synthesis method, and the dynamic responses of the reducer-order model under calibration loads are simulated and used to create the dataset. An identification model for bolt looseness of the tower structure based on convolutional neural networks driven by the acceleration sensors is constructed.

An identification model for bolt looseness of the tower structure based on convolutional neural networks driven by the acceleration sensors is constructed and the applicability of the model is investigated. It is shown that the proposed method has a high identification accuracy and strong robustness to data noise and data missing. Meanwhile, the method is less dependent on the number and location of sensors and is easier to apply in real transmission lines.

This paper proposes a data-driven identification method for bolt looseness of a complicated tower structure based on reduced-order models and numerical simulations. Non-linear relationships between equivalent stiffness of bolted joints and bolt preload depicting looseness are obtained and reduced-order model of tower structure with bolt looseness is established. Finally, this paper investigates applicability of identification model for bolt looseness.