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Article
Publication date: 31 July 2009

Chien‐Yi Huang, Ming‐Shu Li, Chen‐Liang Ku, Hao‐Chun Hsieh and Kung‐Cheng Li

The purpose of this paper is to discuss the chemical characterization of failures and process materials for microelectronics assembly.

Abstract

Purpose

The purpose of this paper is to discuss the chemical characterization of failures and process materials for microelectronics assembly.

Design/methodology/approach

The analytical techniques used for chemical structures and compositions including Fourier transform infrared spectrometer (FTIR), scanning electron microscopy, and energy‐dispersive X‐ray spectroscopy are conducted.

Findings

The residues on the golden finger are identified to be the flux used in the assembly processes. Besides, the contaminants on the processed and incoming connector pins are verified to be polyamides (–CONH functional groups) from housing material's residue. Three liquid fluxes used in wave soldering are analyzed by their chemical structure. One flux showing the OH groups at 3430 cm−1 indicates higher acid contents. This consists with the acidic values specified by the supplier. Also, the solder mask under study has ever appeared peeled‐off issue. The FTIR spectra results indicated 62.2 percent degree of curing while vendor's spec is above 70 percent.

Originality/value

The establishment of the Infrared spectra database for fluxes and process materials help determine the root cause of the contaminants to reduce re‐occurrence of similar problems and thus enhance the manufacturing capability. The infrared spectrophotometry technique can be used by professional original design manufacturing and/or electronics manufacturing service, providers to investigate board/component defects during product pilot run stage and volume production.

Details

Microelectronics International, vol. 26 no. 3
Type: Research Article
ISSN: 1356-5362

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Article
Publication date: 1 October 2005

Z.H. Gao, J.Y. Gu, X‐M. Wang, Z.G. Li and X.D. Bai

To evaluate the competing reaction of isocyanate with cellulose and water which can provide direction for further studies on bonding and curing reactions of isocyanate with wood.

Abstract

Purpose

To evaluate the competing reaction of isocyanate with cellulose and water which can provide direction for further studies on bonding and curing reactions of isocyanate with wood.

Design/methodology/approach

Two modern analytical techniques, Fourier transform infra‐red (FTIR) and X‐ray photoelectron spectroscopy (XPS), were used. The FTIR was used to identify the products of the reaction of phenyl isocyanate (PI) with alcohol, water, and cellulose; while the XPS was used to evaluate the proportions of isocyanate that reacted with water or cellulose when PI reacted with cellulose at different moisture contents (MCs), respectively.

Findings

Methods for the IR identifications of reaction results of PI with n‐propanol, water, and cellulose, in which the reactions of PI with water and PI with cellulose resulted in N,N′‐diphenylurea and carbamate, respectively, were developed. It was discovered that the extent of reaction of isocyanate and cellulose decreased with increasing cellulose MC, and 92.98 per cent isocyanate reacted with water when 9.78 per cent MC was reached. It was confirmed that the products of the PI reaction were distributed mainly on the surface of the cellulose particles.

Research limitations/implications

The study only focused on the reaction of PI. However, the industrial isocyanates, e.g. methylene diphenyl diisocyanate (MDI), polymerized methylene diphenyl diisocyanate (p‐MDI) that have complexities in chemical structures and components, make analyses with FTIR and XPS impossible.

Practical implications

The paper provides some instructive information about the isocyanate reaction that will help understanding the characteristics of isocyanate and guiding the design of technology bonding isocyanate to fibre, wood, etc.

Originality/value

The application of FTIR and XPS for evaluating the reaction of isocyanate with cellulose having different MCs was novel and may be used as a reference for other relevant studies.

Details

Pigment & Resin Technology, vol. 34 no. 5
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 1 December 1998

C.G.L. Khoo and Johan Liu

Three common glob top encapsulant materials, two epoxy‐based, and one silicone‐based, were characterized prior to temperature cycling using differential scanning…

Abstract

Three common glob top encapsulant materials, two epoxy‐based, and one silicone‐based, were characterized prior to temperature cycling using differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), dynamic mechanical spectroscopy (DMS), gas chromatograph‐mass spectrometry (GC‐MS), and Fourier transform infrared spectroscopy (FTIR). After cycling between ‐55 to +125°C, for 1,000 cycles, the same samples were again analysed using DMS and FTIR. For the epoxy‐based samples, the DMS results indicated that temperature cycling in a humid environment can seriously affect the physical and mechanical properties of these samples. FTIR data also indicated that the molecular changes in the epoxy‐based samples appeared quite extensive after cycling, indicating a high level of degradation on the molecular scale. On the other hand, the silicon‐based glob top appeared to have survived the temperature cycling quite well.

Details

Circuit World, vol. 24 no. 4
Type: Research Article
ISSN: 0305-6120

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Article
Publication date: 6 January 2012

Xinying Lv, Rongguo Wang, Wenbo Liu and Long Jiang

The purpose of this paper is to investigate the effect of thermal‐oxidative aging at 150°C on the mechanical properties of carbon fibre reinforced bismaleimide composites.

Abstract

Purpose

The purpose of this paper is to investigate the effect of thermal‐oxidative aging at 150°C on the mechanical properties of carbon fibre reinforced bismaleimide composites.

Design/methodology/approach

Composites specimens after thermo‐oxidative aging at 150°C for various times (up to 1,000 h) were investigated by scanning electron microscopy (SEM) for fracture morphology, Fourier transform infrared (FTIR) spectroscopy for chemical structures, and flexural strength test and inter‐laminar shear strength (ILSS) test for mechanical properties.

Findings

The results indicated that the mechanical properties of carbon fibre/BMI composites were affected significantly by testing temperature rather than by aging time. SEM results showed that the good adhesion of fibre and matrix resulted in the better mechanical properties. The composites showed lower flexural strength and ILSS at 150°C due to the viscoelastic behaviour of matrix resin. The FTIR spectra confirmed the decomposition of crosslinked maleimide occurred just on the surface of composites during various aging times.

Research limitations/implications

Results indicated that carbon fibre/BMI composites had excellent heat resistance and aging resistance.

Practical implications

Due to their excellent thermal and mechanical properties, the carbon fibre/BMI composites show greater potential for their applications in some extreme fields such as aerospace and machine.

Originality/value

The paper investigates the relationships of the fracture morphologies of composites and chemical structures of matrix resin to the mechanical properties after thermo‐oxidative aging.

Details

Pigment & Resin Technology, vol. 41 no. 1
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 1 July 2014

Yanhua Zhang, Jun Cao, Haiyan Tan and Jiyou Gu

The mechanisms of the deblocking reaction of the polyurethane with blocking agent were investigated in detail relatively using thermogravimetric analysis (TGA), Fourier…

Abstract

Purpose

The mechanisms of the deblocking reaction of the polyurethane with blocking agent were investigated in detail relatively using thermogravimetric analysis (TGA), Fourier transform infrared spectrometry (FTIR) and X-ray photoelectron spectroscopy (XPS). This kind of method for polyurethane as the application of wood adhesives can provide the conditions of application and the main theoretical basis.

Design/methodology/approach

The blocking rate and latex particle size distribution were determined using the titrimetric analysis and the laser particle analysis, respectively. TGA, FTIR, XPS and differential scanning calorimetry were used to investigate the deblocking temperature and time of the blocked isocyanate in detail.

Findings

The results indicated that the blocking rate was approximately 97 per cent and the average particle size was 360 nm. The results of laser particle analysis have confirmed that the dispersivity of the blocked polyurethane emulsion was good. XPS results showed that the amount of –O = C-N-benzyl groups increased with an increasing deblocking temperature and subsequently reached equilibrium. In summary, the blocked isocyanate was deblocked at temperatures ranging from 50 to 90°C.

Research limitations/implications

An important approach in future wood adhesive work would be to gain access to man-made board application data.

Practical implications

The paper provided some useful information about deblocking mechanisms of blocked polyurethane that would be helpful to guide applied practical applications as wood adhesive.

Social implications

To promote China’s wood processing technology progress and solve the problem of shortage of the natural quality of wood is of important practical significance.

Originality/value

The paper is the first to use the XPS characterisation method to characterise deblocking polyurethane solution.

Details

Pigment & Resin Technology, vol. 43 no. 4
Type: Research Article
ISSN: 0369-9420

Keywords

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Article
Publication date: 22 September 2021

Altaf H. Basta, Vivian F. Lotfy and Aya M. Salem

This study aims to motivate the application of some low-cost minerals in synthesizing nanoparticles as effective additives on the performance of liquid crystal (LC…

Abstract

Purpose

This study aims to motivate the application of some low-cost minerals in synthesizing nanoparticles as effective additives on the performance of liquid crystal (LC) hydroxypropyl cellulose (HPC) nanocomposite film, in comparison with carbon nanoallotrope.

Design/methodology/approach

Metallic nanoparticles of vanadium oxide, montmorillonite (MMT) and bentonite were synthesized and characterized by different techniques (Transmission electron microscopy [TEM], X-ray diffraction [XRD] and Fourier transform infrared [FTIR]). While the XRD, FTIR, non-isothermal analysis thermogravimetric analysis, mechanical analysis, scanning electron microscope and polarizing microscope were techniques used to evaluate the key role of metallic nanoparticles on the performance of HPC-nanocomposite film.

Findings

The formation of nanoparticles was evidenced from TEM. The XRD and FTIR measurements of nanocomposite films revealed that incorporating the mineral nanoparticles led to enhance the HPCs crystallinity from 14% to 45%, without chemical change of HPC structure. It is interesting to note that these minerals provide higher improvement in crystallinity than carbon nanomaterials (28%). Moreover, the MMT provided film with superior thermal stability and mechanical properties than pure HPC and HPC containing carbon nanoparticles, where it increased the Ea from 583.6 kJ/mol to 669.3 kJ/mol, tensile strength from 2.25 MPa to 2.8 MPa, Young’s modulus from 119 MPa to 124 MPa. As well as it had a synergistic effect on the LC formation and the birefringence texture of the nanocomposites (chiral nematic).

Research limitations/implications

Hydroxylpropyl cellulose-nanocomposite films were prepared by dissolving the HPC powder in water to prepare 50% concentration, (free or with incorporating 5% synthesized nanoparticles). To obtain films with uniform thickness, the prepared solutions were evenly spread on a glass plate via an applicator, by adjusting the thickness to 0.2 mm, then air dried.

Practical implications

These minerals provide higher improvement in crystallinity than carbon nanomaterials (28%), moreover, the MMT and bentonite provided films with superior thermal stability than pure HPC and HPC containing carbon nanoparticles. The mineral nanoparticles (especially MMT nanoclays) had a synergistic effect on LC formation and the birefringence texture of the nanocomposites (chiral nematic).

Social implications

This study presents the route to enhance the utilization of claystone available in El-Fayoum Province as the precursor for nanoparticles and production high performance LC nanocomposites.

Originality/value

This study presents the route for the valorization of low-cost mineral-based nanoparticles in enhancing the properties of HPC-film (crystallinity, thermal stability, mechanical strength), in comparison with carbon-based nanoparticles. Moreover, these nanoparticles provided more ordered mesophases and, consequently, good synergetic effect on LCs formation and the birefringence texture of the HPC-films.

Details

Pigment & Resin Technology, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 8 November 2011

Zongyan Zhao, Zhenhua Gao, Wenbo Wang and Mingruo Guo

The purpose of this paper is to investigate the effects of the components of whey‐protein based aqueous polymer‐isocyanate (API) adhesives on the bond strength.

Abstract

Purpose

The purpose of this paper is to investigate the effects of the components of whey‐protein based aqueous polymer‐isocyanate (API) adhesives on the bond strength.

Design/methodology/approach

The bond test (according to the JIS K6806‐2003 standard), Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) were used to characterise the whey‐protein based API adhesives with various formulations and processing technologies.

Findings

The good bond strength of the optimised whey‐protein based API adhesive was attributed to the formation of strong chemical bonds in the bondline and to the additions of polyisocyanate, polyvinyl alcohol (PVA) and nano‐CaCO3 powder that improved adhesive cohesive strength by either chemical crosslinks or mechanical interlocking. The blending procedures of whey protein, PVA, polyvinyl acetate (PVAc) and p‐p‐MDI had great impacts on the performances of the whey‐protein based API adhesives.

Research limitations/implications

SEM micrographs showed that the effects of blending processes on the bond strength, pot life and colour might be attributed to the particle size of hydrophobic p‐MDI droplet and p‐MDI distribution in the protein‐PVA matrix.

Practical implications

The study lays the foundations of the formulation design and the processing technology for preparing whey‐protein based API adhesives.

Originality/value

The effects of the components of whey‐protein based API adhesives and the effects of blending processes on the bond strength were investigated by means bond strength evaluation, FTIR and SEM analyses; whey protein is utilised successfully to prepare novel API adhesives for structural uses.

Details

Pigment & Resin Technology, vol. 40 no. 6
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 25 May 2010

R.X. Cheng and J.Y. Gu

The purpose of this paper is to improve the adhesion of Larch wood, by conducting a study of hydrogen peroxide treatment on Larch wood surfaces.

Abstract

Purpose

The purpose of this paper is to improve the adhesion of Larch wood, by conducting a study of hydrogen peroxide treatment on Larch wood surfaces.

Design/methodology/approach

Effect of surface treatment of Larch by H2O2 on the adhesion of Larch wood, as indicated by compression shear strength, was examined in this paper. Surface properties of Larch wood, such as contact angle were evaluated. Shear strength tests for measuring adhesion of Larch blocks were conducted. Fourier transform infrared (FTIR) analysis was employed to examine the chemical functionality of the untreated and treated Larch surface.

Findings

It is found that hydrogen peroxide treatment improved the adhesion of Larch glued laminated timber. The dry compression shear strength of Larch glued laminated timber treated with H2O2 solution is increased by 19.7 per cent compared with the untreated Larch glued laminated timber. FTIR results showed that the intensity of absorption band at 1,730 cm−1 for H2O2 solution‐treated Larch increased as compared with the untreated Larch wood. The results of contact angle showed that wettability of Larch treated with H2O2 solution increased markedly compared with the untreated Larch.

Research limitations/implications

The improvement of adhesion as a result of hydrogen peroxide treatment mainly applies to radial Larch surface.

Practical implications

This study provided a simple and practical solution to improving the adhesion of Larch laminated timber glued with water‐based Polymer Isocyanate (WPI) adhesive. Such a hydrogen peroxide surface treatment may be applied to other types of wood.

Originality/value

This method of improving the adhesion of Larch glued laminated timber can be used for other Larch products glued with WPI.

Details

Pigment & Resin Technology, vol. 39 no. 3
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 8 June 2018

Rokbi Mansour, Ati Abdelaziz and Aiche Fatima Zohra

The literature reveals there is a limited knowledge regarding the extraction of long natural fibers, in particular those extracted from leaves. This investigation aims to…

Abstract

Purpose

The literature reveals there is a limited knowledge regarding the extraction of long natural fibers, in particular those extracted from leaves. This investigation aims to present the extraction process and the characterization of long natural cellulose fibers from doum palm leaves (Hyphaene thebaica L.), with properties suitable for polymeric composite materials and textile applications.

Design/methodology/approach

The resulting H. thebaica L. fibers were identified using Attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy, X-ray diffraction (XRD), thermogravimetric analysis (TGA) and scanning electron microscopy (SEM). The physical properties of the extracted fibers were measured to estimate the reliability of extraction conditions. Mechanical properties were evaluated to determine ultimate strength, Young’s modulus and strain-at-failure of the fibers of the doum leaves.

Findings

The following properties of the doum palm are listed in this paper: physical properties of doum palm fibers (H. thebaica L.), TGA, XRD of doum palm fibers, tensile properties of doum palm fibers and surface morphology of doum palm fibers.

Research limitations/implications

Like synthetic fibers, the inclusion of short or long natural fibers into the polymer matrix can increase tensile, flexural and compressive strengths of these matrixes. Compared to the short-length natural fibers, longer-length fibers provide better reinforcements and therefore accord higher performances to the composites. Long fibers can also provide exceptional opportunities to develop a new class of advanced lightweight composites and have the potential to rival glass fiber in the manufacture of composite materials, using matrix materials, such as polypropylene, epoxy and phenolic resins.

Originality/value

The following values are presented in this paper: density of doum palm fibers = 1.14-1.40 g/cm², linear density (Tex) = 33.10 ±11.5, equivalent diameter (µm) = 178.72 ± 41.7, diameter (µm) = 137.02-220.42, tensile strength (MPa) = 124.84-448.10, Young’s modulus (GPa) = 8.06-19.59, strain-at-failure (%) = 0.81-2.86.

Details

Research Journal of Textile and Apparel, vol. 22 no. 3
Type: Research Article
ISSN: 1560-6074

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Article
Publication date: 20 April 2020

Hala A.M. Afifi, Heba Sayed Galal and Rushdya Rabee Ali Hassan

The purpose of this paper is to identify the pigments, mediums and ground layer used during the late era of ancient Egyptian civilization through the analysis of mummy…

Abstract

Purpose

The purpose of this paper is to identify the pigments, mediums and ground layer used during the late era of ancient Egyptian civilization through the analysis of mummy Cartonnage based on the use of multiple analysis, such as electron microscopy, X-rays, scanning electron microscopy (SEM) and Fourier transform infrared (FTIR).

Design/methodology/approach

This study analyzed some fragments from a painted cartonnage of a mummy date back to the late period. Light microscopy, X-ray diffraction analysis, FTIR analysis and investigation of the surface morphology by SEM were used to identify the chemical and anatomical structure of cartonnage.

Findings

The results clearly showed use of copper and extracted gold from the veins of the quartz to get the golden pigment, but it is full of voids which were a major cause of the degradation.

Originality/value

The study is the first of its kind on the components of this cartonnage in Saqqara stores.

Details

Pigment & Resin Technology, vol. 49 no. 4
Type: Research Article
ISSN: 0369-9420

Keywords

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