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This study aims to prepare UV protection and hydrophobic fabric through modifying cotton fabric by graphene oxide and silane coupling agent. The graphene oxide and silane coupling agent (KH570) are anchored on the cotton fabric by a stable chemical bond.

Graphene oxide was prepared by modified Hummers method. The fabric sample was treated with graphene oxide and silane coupling agent KH570 using simple dipping-padding-drying method. The effects of the dosage of graphene oxide, silane coupling agent KH570 and curing temperature were determined by single variable experiment and orthogonal experiment, The UVA and UVB transmittances in ultraviolet light of the sample fabric were characterized, and the contact angle test method with water was used to indicate the hydrophobicity of the sample fabric. The structure and surface of the fabric were analyzed using Fourier-transform infrared spectroscopy and scanning electron microscopy.

The cotton fabric was successfully modified by graphene oxide and silane coupling agent KH570. Compared with the untreated fabric, the surface of the fabric was smooth, and there was no gap on the fiber. The graphene oxide, silane coupling agent KH570 and cotton fabric combined tightly. The UPF value of the modified fabric was 50+, and the contact angle reached 138.1°. It had excellent UV protection and hydrophobic properties.

Although graphene oxide and silane coupling agents KH570 had successfully endowed the cotton fabric with good UV protection and hydrophobic properties, graphene oxide and silane coupling agent KH570 are expensive and used in large quantities. There are certain limitations in the actual life and production process.

After treating with silane coupling agent, the hydrophilic fabric treated with graphene oxide is being translated into hydrophobic, and graphene oxide bonded with cotton. The modified fabrics also have excellent UV protection. This fabric can be used for outdoor sports such as clothes and tents.

Cotton fabric treated with graphene oxide generally by simple dip-dry-cure method is hydrophilic and graphene oxide is easy to drop. The usage of silane coupling agent KH570 as a crosslinking agent to link graphene oxide and cotton fibers has not been reported yet. The modified fabrics have both UV protection and hydrophobic properties.

The purpose of this paper is to evaluate the water vapour permeability and mechanical properties of a solventless epoxy – nano‐platelet nano‐composite system compatibilised with an amino‐silane.

The performance of a nano‐platelet reinforced coating composite was studied with reference to the water vapour permeability and mechanical properties. The effect of addition of coupling agent on these properties was also studied.

The addition of nano‐platelets to the solventless epoxy system resulted in an increased water vapour permeability which was reduced on the addition of coupling agent. The talc‐based films showed a better performance as compared to the montmorillonite based coatings. The mechanical properties of the films increased though the addition of coupling agent showed a larger increase. The gloss of the coatings was compromised on addition of nano‐particles. Comparing coupling agents, the primary amine based silane showed better performance and lower tactoid formation as compared to the secondary amino silane based coupling agent.

The addition of nano‐particles to solventless and other eco‐friendly coatings needs to be studied further. Various other coupling agents could be studied to further improve the performance of these coatings.

The formulation developed could be used to reduce the water vapour permeability and performance of solventless epoxy coatings, which could be used as anti‐corrosive coatings.

The study of performance of nano‐particles in solventless epoxy coatings and their effect on water vapour permeability could increase performance of these reduced VOC coatings.

Studies on the surface modification of sodium‐aluminium silicate P‐820 using silane coupling agents are described. The best modifiers were selected, which induced a change of the silicate surface from hydrophilic to hydrophobic. Physicochemical analyses of the modified silicate were performed. The methods of evaluating silicate surface modification degree were presented. The degree of hydrophobization of silicate surface was determined by a calorimetric method. Near infra‐red spectroscopy (NIR) was used to determine the degree of condensation of the silicate surface silanol groups. Studies on morphology and microstructure using transmission electron microscopy (TEM) were performed. Attempts were made to apply the unmodified and modified sodium‐aluminium silicate P‐820 as filler and pigment in silicate and dispersion paints.

This paper presents results on adding silane coupling agents to the underfill encapsulant to enhance the rheology and wetting of the underfill. These results include rheology measurements, contact angle measurements, and in situ flows using a simulated test chip on an FR4 with solder mask substrate. Three properties of the underfill encapsulant that can affect the mechanical reliability of the die and substrate assembly are: CTE; elastic modulus; and adhesion to the die and substrate surfaces. The approach taken in this paper is to add silane coupling agents with different chemistries to the underfill encapsulant to provide interfacial coupling of the underfill material to different die and substrate materials. This paper presents results on the enhancement of the adhesion of underfill encapsulant to silicon (Si), silicon nitride (SiN) die passivation, benzocyclobutene (BCB) die passivation, and solder mask surfaces. The adhesion strength was measured by die shear testing.

The purpose of this paper is to improve binding force between the coating and the steel substrate by using chemical modification on the steel surface; at the same time, it can also increase the corrosion resistance of the coating.

The main components of the conversion film include tannic acid, sodium molybdate and silane coupling agent KH560. After the preparation was completed, the samples were tested and analyzed, including surface morphology, conversion film components, bonding force with organic resins and corrosion resistance. Finally, it drew a conclusion that the conversion film can greatly improve the bonding strength of the steel substrate and epoxy resin.

When the content of tannic acid is 4 g/L meanwhile the content of KH560 is 20 g/L, the conversion film has the strongest binding force with epoxy resin, from 2.15 Mpa of untreated steel to 4.60 Mpa, growth of 140 per cent. At the same time, the resulting conversion film also improves the corrosion resistance of the steel surface by a small margin.

A method of enhancing the bond between an epoxy coating and steel is provided. Verify the mechanism of this method.

Two types of amorphous silica namely, the precipitated silica and the pyrogenic silica, were studied. The surfaces of such silica were modified with silane coupling agents such as 3‐aminopropyltriethoxysilane, N‐2‐(aminoethyl)‐3‐aminopropyltrimethoxysilane and 3‐ureidopropyltrimethoxysilane. Pigments were obtained by the adsorption of organic dyes, C.I. Reactive Blue 19 and C.I. Acid Green 16, onto the modified silica surface. Structural properties of the modified silica and the pigments obtained were evaluated using scanning electron microscopy, zeta potential analysis and particle size measurement techniques. Moreover, colour of the pigments obtained was evaluated using the CIE L *a*b* colour space system. The specific surface area of the pigment obtained was estimated using the BET method.

The purpose of this paper is to investigate the effect of different PHS on the surface chemistry of fumed silica treated with aminopropyltrimethoxysilane (APTMS).

The reaction conditions involved variation of pH ranging from acidic to alkaline. Different analytical techniques including FT‐IR spectroscopy, thermogravimetric analysis (TGA), CHN and Zeta potential analyses were employed to investigate the surface chemistry of treated particles. In addition, the stability of silanised silica dispersions were studied using turbidimetric and rheometric measurements.

It was revealed that in all conditions silica was more or less chemically grafted by the silane. When the pH of treating bath was adjusted to 1‐2 prior and during the reaction, 58 percent grafting was observed, as obtained by CHN and TGA analyses. At very alkaline conditions, however, the grafting content declined to 29 percent. The variations in grafting were dependent on the silane hydrolysis and its further condensation with the silica surface. Zeta potential measurements showed a drastic change from −7.1 mv to +18.01 mv (at pH 7) for the untreated particle and the one with the highest grafting, respectively. The dispersion stability of differently treated particles varied in solvents with different Hansen solubility parameters (HSP). Moreover, due to the variations of surface chemistry of particles, their rheological behaviours were significantly influenced.

The results obtained in this work showed that the surface chemistry of fume silica could be tuned with treating method. The highest content of grafting led to a better dispersion in solvents having greater hydrogen bonding component and to an inferior dispersion in solvents with higher polar component.

The surface character of titanium dioxide (rutile) was altered by surface modification. Silane coupling agents were used as modifiers. Physicochemical properties of the obtained products were evaluated. Effects of the modifier concentration on changes in hydrophilic/hydrophobic properties of the surface were estimated. The tendency to form primary and secondary agglomerate structures was defined using dynamic light scattering and examining morphology and surface structure with the use of scanning electron microscopy. Specific surface area and pore volume were also measured in unmodified and modified titanium white.

The purpose of this paper is to investigate the effects of coupling agents on the structure and properties of the nanocomposite films and clarify their mechanism. Polyimide (PI)/Al₂O₃ nanocomposite films were prepared using different coupling agents.

Poly(amic acid) (PAA) was firstly synthesised from appropriate pyromellitic diannanocomposite and oxydianiline in N‐dimethylacetamide. Calculated amount of nano‐Al₂O₃ particles modified by different coupling agents (KH550, KH560, KH570 and AE3012) were added to PAA solution by an ultrasonic‐mechanical method and PI/nano‐Al₂O₃ film was fabricated by heat curing. The microstructure, thermal stability, mechanical properties and electric breakdown strength of the films were characterised.

The addition of coupling agents could greatly improve the dispersion homogeneity of Al₂O₃ nano‐particles in PI matrix. Results of corresponding characterisations indicated that both the thermal stability and mechanical properties of PI/Al₂O₃ nanocomposite film with KH550 were greater/better than others, while AE3012 could improve the electric breakdown strength.

In the present discussion, the effects of different coupling agents, KH550, KH560, KH570 and AE3012, were investigated. Results of this research work would be beneficial to an in‐depth understanding on the relationship between microstructure and properties of PI composites, and further promote the development of the high‐performance PI insulating materials.

The four coupling agents, KH550, KH560, KH570 and AE3012, were firstly used to disperse the nano‐Al₂O₃ particles in PI matrix. The effects of coupling agents on microstructure and properties of composites were discussed by the authors in detail.