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The 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.

Ketone, 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.

The 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.

The 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.

This 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.

Vinyl 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.

The purpose of this paper is to report the synthesis of resins having conducting and fluorescence properties, with carbazole and oligocarbazole with a one step method of in situ modification of ketonic resin. Cyclohexanone‐formaldehyde (CFR), and acetophenone‐formaldehyde (AFR) resins were in situ modified with carbazole in the presence of sodium hydroxide.

Carbazole modified ketonic resins were synthesised by the condensation reaction of Cz, formaldehyde and ketone. Oligo carbazole was synthesised by redox reaction of carbazole and ceric ammonium nitrate (CAN). Then, for the in situ modification of oligo carbazole modified ketonic resin, reaction mixture of oligocarbazole carbazole was added to the cyclohexanone/formaldehyde solution.

The carbazole modified cyclohexanone‐formaldehyde and acetophenone formaldehyde resins have conductivity values of 10⁻⁵‐10⁻⁶ S/cm and may be considered as semi‐conductive ketonic resins. These new carbazole modified ketonic resins (CCzFR, ACzFR) have fluorescence properties.

This study focused on obtaining a conductive and fluorescence resin using a carbazole monomer which is an insulator.

This study provides technical information for the synthesis of fluorescence comonomer.

New CCzFR, ACzFR comonomers were synthesised. These comonomers have higher Tm values than CFR and AFR alone and also have fluorescence property.

Cyclohexanone‐formaldehyde resins (CF‐Rs) were in situ modified with aniline, 4‐aminodiphenylamine, and N‐N′‐diphenyl‐1,4‐phenylene diamine in presence of sodium hydroxide. The purpose of this paper is to report the synthesis of conducting resins with aniline, dimer and trimer aniline, with a one‐step method of in situ modification of ketonic resin. The roles of ketone, aniline concentration, the conductivity of the product are investigated.

Ketone, formalin (37 per cent aqueous solution), aniline or oligoaniline were mixed and 20 per cent aqueous NaOH solution was added to produce the resin.

The aniline‐modified (CF‐Rs) were found to have conductivity values of 10⁻³‐10⁻⁵ S/cm and may be considered as conductive ketonic resin.

The reaction mixture must be stirred continuously. Amount of aniline and oligoaniline is limited. Subsequently, 37 per cent formalin was added dropwise in total while refluxing. The amount of aniline is limited since the formed resin may become insoluble in common organic solvents.

This work provides the application of conducting resins. The modified resins containing aniline groups may also promote the adhesive strength of a coating and corrosion inhibition to metal surfaces.

Aniline formaldehyde, N‐N′‐diphenyl‐1,4‐phenylenediamine‐formaldehyde, aniline‐ and oligoaniline‐modified (CF‐Rs) have been synthesised in the presence of a base catalyst. These resins are conductive resins and the ketonic resins formed have physical properties of both aniline‐formaldehyde resins such as conductivity.

The purpose of this paper is to investigate the electrical conductivity and corrosion protection properties of a conductive coating composed of epoxy resin and carbon black in a sodium chloride (NaCl) solution.

The conductive coating was prepared by combining epoxy resin, hardener, and carbon black. The electrical conductivity of the paint was studied with a DC current‐voltage meter and field emission scanning electron microscopy. The corrosion protection properties of the paint were characterized by open circuit potential measurements and electrochemical impedance spectroscopy.

The highest conductivity observed was 4.23×10⁻⁴ Scm⁻¹ for the coating containing 20 wt% carbon black. The coating protected mild steel in a 3.0 percent NaCl solution for up to five days.

The results shown in this paper provide an insight into conductive paint and corrosion protection for future industrial applications and development.

The purpose of this study is to explore the synthesis of novel conductive photo-resins to produce flexible conducting composites for use in additive manufacturing. By using direct ink writing (DIW) additive manufacturing, this study aims to explore the fabrication of multimaterial devices with conductive and insulating components. Using digital light processing (DLP) additive manufacturing, this study aims to fabricate detailed objects with higher resolution than material extrusion 3D printing systems.

In this paper, several photocurable conducting resins were prepared for DIW and DLP additive manufacturing. These resins were then cured using 405 nm near UV light to create intrinsically conductive polymer (ICP) composites. The electrochemical properties of these composites were analysed, and the effect of co-monomer choice and crosslinking density was determined. These results determined a suitable resin for subsequent additive manufacture using DIW and DLP. These 3D printing techniques were used to develop flexible conducting devices of submillimetre resolution that were fabricated with unmodified, commercially available 3D printers.

Cyclic voltammetry and volume conductivity analysis of the conducting resins determined the most conductive resin formula for 3D printing. Conductive devices were fabricated using the two 3D printing techniques. A multimaterial soft conducting device was fabricated using DIW, and each conducting component was insulated from its neighbours. DLP was used to fabricate a soft conducting device with good XY resolution with a minimum feature size of 0.2 mm. All devices were prepared in unmodified commercially available 3D printers.

These findings have value in the development of soft robotics, artificial muscles and wearable sensors. In addition, this work highlights techniques for DIW and DLP additive manufacturing.

Several original conducting resin formulae were developed for use in two 3D printing systems. The resulting 3D-printed composites are soft and flexible while maintaining their conductive properties. These findings are of value to both polymer chemists and to the field of additive manufacturing.

This review paper aims to provide a better understanding of formulation and processing of anisotropic conductive adhesive film (ACF) material and to summarize the significant research and development work for the mechanical properties of ACF material and joints, which helps to the development and application of ACF joints with better reliability in microelectronic packaging systems.

The ACF material was cured at high temperature of 190°C, and the cured ACF was tested by conducting the tensile experiments with uniaxial and cyclic loads. The ACF joint was obtained with process of pre-bonding and final bonding. The impact tests and shear tests of ACF joints were completed with different aging conditions such as high temperature, thermal cycling and hygrothermal aging.

The cured ACF exhibited unique time-, temperature- and loading rate-dependent behaviors and a strong memory of loading history. Prior stress cycling with higher mean stress or stress amplitude restrained the ratcheting strain in subsequent cycling with lower mean stress or stress amplitude. The impact strength and adhesive strength of ACF joints increased with increase of bonding temperature, but they decreased with increase of environment temperature. The adhesive strength and life of ACF joints decreased with hygrothermal aging, whereas increased firstly and then decreased with thermal cycling.

This study is to review the recent investigations on the mechanical properties of ACF material and joints in microelectronic packaging applications.

The SiC reinforced Al composite is perhaps the most successful class of metal matrix composites (MMCs) produced to date. They have found widespread application for aerospace, energy, and military purposes, as well as in other industries – for example, they have been used in electronic packaging, aerospace structures, aircraft and internal combustion engine components, and a variety of recreational products. In all these applications, welding plays a vital role. Little attention has been paid to SiC reinforced aluminium matrix composites joined by gas tungsten arc (GTA) welding. The purpose of this paper is to outline the manufacturing method for producing MMCs, GTA welding of MMCs and pitting corrosion analysis of welded MMCs.

This paper focuses upon production and welding of metal matrix composites. The welded composites have been treated at elevated and cryogenic temperatures for experimental studies. Pitting corrosion analysis of welded plates was carried out as per Box Benkehn Design.

From the results, it should be noted that maximum pitting resistance was observed with MMCs containing 10% SiC treated at cryogenic temperature. Corrosion resistance of welded composites treated at elevated temperature was found to be higher than that of as‐welded and at cryogenic temperature treated composites. The pitting potential increases with increase in % SiC to certain level and decreases with further increase in % SiC. Corrosion potential of composites treated at elevated temperature is high compared to other composites. Maximum pitting resistance is observed when the welding current was kept at 175 amps for 10% addition of SiC in LM25 matrix treated at cryogenic temperature.

The paper outlines the manufacturing method for producing MMCs, GTA welding of MMCs and pitting corrosion analysis of welded MMCs. The results obtained may be helpful for the automobile and aerospace industries.

The purpose of this study is to investigate the reliability of flex-on-board (FOB) interconnection connected with an anisotropic conductive paste (ACP), which is prepared by dispersing nickel balls in the epoxy-curing system.

Differential scanning calorimetry was used to evaluate the curing characteristics of the paste. And the contact resistances of bonding joints and 90º peel adhesion were tested before and after high temperature and high humidity test (85°C, 85% humidity), thermal cycling (−45°C∼125°C, 30min/cycle) and pressure cooker test (PCT, 121°C, 100% humidity 2 atm) to evaluate the flex on board (FOB) interconnection reliability.

It is found that FOB test vehicles have been successfully bonded by using ACP for the first time. And the ACP bonding joint of FOB has good reliability and can meet the requirements of FOB interconnection. Compared with conventional anisotropic conductive film (ACF), this ACP interconnection provides higher adhesion strength, higher joint current carrying capability and higher reliability performance and lower cost for FOB interconnection.

ACP is applied in the interconnection of FOB. It has the higher reliability performance and lower cost for than the conventional ACF.

The purpose of this paper is to obtain a conductive polymer by using a fluorescence comonomer which is an insulator. In this study, methyl ethyl ketone formaldehyde resin (MEKFR) modified with carbazole‐9‐carbonyl chloride (CzCl) was synthesised via hydroxyl groups of MEKFR. Electrochemical polymerisation of Cz‐MEKFR comonomer was carried out potentiostatically and a green, conductive polymer P(Cz‐MEKFR) was obtained. The advantages of obtaining alternative structure of P(Cz‐MEKFR) to the random copolymer were reported.

Cz‐MEKFR comonomer was synthesised by the esterification reaction of CzCl and hydroxyl groups of MEKFR. Then, for the electrochemical polymerisation, potentiodynamic electrodeposition of Cz‐MEKFR comonomer in dichloromethane on to Pt was carried out. Electrochemical activities of polymers were tested by electrochemical methods (i.e. polarization curves and cyclovoltammetry). UV‐visible, NMR, polarization curves, cyclovoltammetric, solid‐state conductivity measurements and in situ spectroelectrochemical methods were performed for the characterization of polymers.

Carbazole‐9‐carbonyl chloride(CzCl) modified MEKFR was synthesised. This new carbazole‐modified resin (Cz‐MEKFR comonomer) has fluorescence property. The ionization potentials (Ip), electron affinity (Ea), optical band gap (Eg), peak potentials (Ep) and doping degree (y) of the polymers were calculated. Results were compared with the PCz homopolymer and the copolymer obtained from the mixture of MEKFR with carbazole P(Cz‐co‐MEKFR).

This study focuses on obtaining a conductive polymer by using a fluorescence comonomer which is an insulator. In order to remove pyridine from comonomer, successively washing with several portions of dilute aqueous H₂SO₄, water‐saturated aqueous sodium hydrogen carbonate, and hot water is necessary.

This work provides technical information for the synthesis of fluorescence comonomer and conducting an alternative polymer.

A new Cz‐CFR comonomer was synthesised. This comonomer has a higher T_m value than MEKFR alone and also has fluorescence property. The band gap of the copolymer is not remarkably lower than polycarbazole. The oxidation potential of P(Cz‐MEKFR) was found to be higher than the PCz homopolymer and the solubility of copolymer is 30 per cent higher than homopolymer.