Papers by Keyword: Compatibility

Abstract: Solder paste is mainly used for welding of resistance, capacitance, integrated circuit (IC) and other electronic components in surface mounted technology (SMT) industry, and the performance of solder paste has a significant impact on the reliability of electronic components. In this paper, processing defects, failure cases and mechanism of electronic components caused by solder paste are analyzed systematically. Improper application of solder paste during welding can lead to numerous processing defects including poor wetting, tombstoning, bridging, solder joint crack, solder ball spattering, corrosion and so on. Finally, an evaluation method of material compatibility is described in this paper, which provides a reference for ensuring the quality of electronic process material and improving the reliability of SMT products.

Abstract: Elastomer is one of the important material for the hoses, sealants and tubes in the components of fuel delivery system in diesel engine vehicles due to the factor of compatibility with diesel fuel. However, concern were arise that presence of alcohol, fatty acid component and other factors such as water content in the alternative fuels which is blended biodiesel fuel and different chemical composition from the diesel fuel may increase further uncertainty to the consumer of diesel engine or diesel engine manufacturers in terms of compatibility issue. Thus this paper intends to assess current and typical test standards on their efficacy of representing the fuel system of diesel engine vehicles. Respectively, ASTM D471 are based on laboratory immersion studies and the experimental conditions are differ from the real service conditions in the fuel system of diesel engine vehicles. Even though number of previous studies regarding to the compatibility of elastomer components has been reported, there is a need to set up the exact material that present in the fuel system of diesel engine vehicles. This is especially right for elastomers since their resistance is mainly depends on their elemental compositions. As such, introduction of the dynamic testing approach that may be applied when assessing the compatibility study between blended biodiesel fuel that simulate the actual fuel system of a diesel engine vehicles before carrying out in the field trials.

Abstract: Compatibility investigation was performed between magnesium stearate and acidic drug compounds (ibuprofen, indomethacin and valproic acid) and acidic pharmaceutical excipients (lactic acid and citric acid) using differential scanning calorimetry (DSC). DSC study indicated the possible incompatibility for the mixture between magnesium stearate and any compounds. Alteration in DSC thermogram was found in all mixtures. The eutectic phenomenon was found in the powder mixture of magnesium stearate and ibuprofen. In addition, the presence of melting endothermic peak of stearic acid in other powder mixtures except the mixture of magnesium stearate and indomethacin indicating breakage of salt form of magnesium stearate. This alteration could relate to the influence on physicochemical properties of drug compounds and pharmaceutical excipients which powder x-ray diffraction (PXRD) and Fourier Transform Infrared Spectroscopy (FT-IR) should be further analyzed to confirm the interactions between compounds.

Abstract: This work was aimed to investigate the effect of alkalization treatment on the fiber-matrix interfacial interaction and hence their compatibility. Kenaf fiber was treated using a 6% NaOH solution for 8 hours. The composites were produced by mixing the treated fiber with PP at various temperatures, duration, and fiber composition. Alteration on the surface chemistry of the fiber was identified by performing FTIR analysis. The surface energy of the treated fiber was mathematically derived from the contact angle measurement results. The compatibility level between treated fiber and PP matrix was visualized through FESEM analysis. Tensile strength tests were also conducted to obtain data necessary for exploring the relationship between the thermodynamic aspects of the fiber-matrix interfacial interaction and the mechanical properties of the composites. The FTIR spectra show that there was significant increase in the %transmittance at wavelength range of 3100-3600 cm^-1 indicating that O-H groups were degraded during treatment. However, the polar component of the surface energy for treated fiber was instead higher compared to the untreated one. The SEM images show that there are no noticeable reduction in the size of the treated fibers as expected. On the other hand, the tensile strength of the PP-treated fibers composites reached its highest value when the matrix were loaded with fibers at the lowest percentage i.e. 5%.

Abstract: Any successful primary cementing operation at elevated temperature condition requires an efficient displacement of fluid surrounding the casing by cement slurry. In such conditions the cement slurry should be designed in such a way that it should be compatible with both cement and drilling mud. To achieve these requirements we designed the cement slurry with weighted spacer. Spacer is a barrier between cement & mud so that they should not mix with each other, also all these fluids should be incompatible inorder to avoid cement aggregation. The displacement efficiency during cementation is directly dependent on discharge rate, but however due to formation fracture pressure constraints, the discharge rate is limited, hence designing spacer becomes very crucial. This phenomenon becomes more pronounced at higher temperature as turbulent flow efficiency reduces due to the presence of weighting agent. The drive of the present work is to identify a suitable viscosifier to avoid settling of weighing agents in spacer and to maintain the stability of rheology admixture at elevated temperature condition. Laboratory tests were performed for compatible deformation and flow of matter with cement slurry-spacer-mud at temperature range (80-140°C) on a rotational viscometer as per the procedure of API RP 10B-2. The volumetric proportions of the cement slurry/spacer and spacer/mud admixtures were prepared with various ratios: 95/5, 75/25, 50/50, 25/75, and 5/95. Rheological compatibility of fluids (cement & spacer and mud & spacer) is evaluated by computing the R-Index Value (R) which is calculated by subtracting highest 100 rpm reading of admixture from highest rpm reading for an individual fluid for the given range of elevated temperature condition. The calculated R-Index Value can then be utilized to comment on fluid compatibility. After finalization of chemical compatibility, rheological hierarchy was achieved by incorporating the friction pressure loss with respect to discharge rate of an individual fluid for the given range of elevated temperature condition. The spacer system used achieved stable compatibility and efficient rheological hierarchy at elevated temperature cementing conditions. In addition, by comparing the results between the two different spacer systems, the role of hydration in attaining rheological compatibility is computed. This study will in turn prove helpful in figuring out the better spacer system which will play a vital role for better displacement and cementation quality.

Abstract: Significant improvement of compatibility in PET/PA6 blends is essential to obtain fibers having enough mechanical strength as well as the comprehensive performance. In this article, copoly (ester-amide 6) was used as compatibilizer to improve the compatibility of PET and PA6. Three copoly (ester-amide 6) s with 5, 10% content of PA6 were prepared by co-polymerization from PTA , EG, as well as PA6 or caprolactam (A6), i.e. polyamide was incorporated both in the form of polymer and monomer, respectively. The sequence length of PET in the copoly (ester-amide 6) s is 33.4, 16.5 and 38.4 for PET-PA6-5%, PET-PA6-10% and PET-A6-5%, respectively, calculated by ¹³C NMR. Then PET/PA6 blend fibers were fabricated by melting spinning of PET and PA6 with 20 %wt addition of PET-PA6-5%, PET-PA6-10% and PET-A6-5%, respectively, to explore the effect of copoly (ester-amide 6) s on compatibility of PET/PA6 blend fibers, where the mass ratio of PET and PA6 is 85/15. DSC results show that the crystallization peaks of PET and PA6 during cooling from the blend melt become adjacent each other with increasing addition of copoly (ester-amide 6) s, even forming fused crystallization of them. It was found from SEM that the size of PA6 phase decreased and the phase boundary became indistinct due to the presence of copoly (ester-amide 6) s. Further more, the glass transition temperatures (T_g) of PET and PA6 closed to each other based on DMA result. Among these three copoly (ester-amide 6) s, PET-A6-5% display the best effect on the compatibility of PET and PA6 blend fiber, suggesting copoly (ester-amide 6) s could play important role in raise the compatibility of PET and PA6 blend.

Abstract: Fluid catalytic cracking (FCC) slurry is a by-product of petrochemical industry rich in aromatics. In this paper, the effect of FCC slurry on the physical properties of SBS modified bitumen was investigated by softening point, penetration, ductility and low temperature flexibility test. The influence of FCC slurry on the compatibility of SBS modified bitumen was evaluated by fluorescence microscope and segregation test. The results show that FCC slurry improves the softening point, penetration, ductility and low temperature flexibility of SBS modified bitumen. Fluorescence microscope showed that FCC slurry promotes the dispersion of SBS in bitumen, which is conducive to the formation of network crosslinking structure of SBS modified bitumen. The segregation test indicated that the compatibility of SBS with bitumen was improved with the content of FCC slurry increasing.

Abstract: Today, due to environmental reasons and limited of fossil resources take many researchers to develop new and renewable materials. Bio-composites which is consisted of synthetic polymers matrix and natural fibres, is one of the alternatives to reducing its problems. Among of natural fibre that has good potential to be used as reinforcement in synthetic polymer matrices is sorghum fibre. However the hydrophilic nature of natural fibers causes it to be incompatible with synthetic polymer matrices which have hydrophobic properties and it’s need to surface modified with particular treatment. The aim of this work was conducted to study the effect of hydrothermal treatment through pressure boiled method by using distilled water in a pressurized stainless steel pan cooking for 5 minutes to defibrillation and hydrophilic properties of stalk sweet sorghum fibres. Evaluation of the experiments was characterized with Field-Emission Scanning Electron microscope (FE-SEM), Fourier Transformation Infra-Red (FTIR) Spectroscopy and sessile drop test instruments, respectively. The experiment was found that using hydrothermal treatments through pressure boiled method led to a removal of binding materials, such as a wax, hemicellulose and lignin, and enhancement the hydrophilic properties of sorghum fibres.

Abstract: This work focuses on the effect of functionality of hydroxylated natural rubber (HNR) and its loading on crystallinity and mechanical properties of polylactic acid (PLA). HNR with hydroxyl groups of 9.09% by mole was prepared from natural rubber latex via epoxidation reaction and then the epoxy rings were cleavaged to produce the hydroxyl groups by using heating at the temperature of 70 °C. HNR4 with the hydroxyl groups of 15.25% by mole was prepared from ONR4 latex with M̅_n of 3.94 × 10³ g/mol and M̅_w of 5.06 × 10³ g/mol. PLA was then blended with the obtained HNR or HNR4 with different weight ratios of PLA:HNR = 70:30 and 60:40. It was found that hydroxylated natural rubber increased the crystallinity of molded PLA sheet from 7.54% to 18.20% for molded PLA:HNR = 70:30 sheet, to 25.16% for molded PLA:HNR = 60:40 sheet and to 24.38% for molded PLA:HNR4 = 70:30 sheet. Morphological analyses revealed the appearance of co-continuous phase in the molded PLA:HNR4 = 70:30 clearer than the molded PLA:HNR = 60:40 and molded PLA:HNR = 70:30 sheets. As a result, it clarified that the higher functionality of hydroxyl groups based on lowering the molecular-weight enhanced the compatibility between PLA and HNR. On the other hand, the mechanical properties of PLA:HNR4 = 70:30 were found to be the highest tensile strength (14.46 MPa), elongation at break (13.62%) and modulus (4.10 MPa) though PLA:HNR = 60:40 gave the highest impact strength of 163.98 J/m. This was believed that the hydroxylated natural rubber enhanced the crystallinity and impact strength of PLA through the interface interaction and/or chemical bonds between hydroxyl groups of HNR and carboxyl terminal groups of PLA.

Abstract: Polypropylene (PP) is one of the biggest petro-polymers, which is used in very wide application nowadays. The environment problem due to materials such as plastics having very long time degradability, and critical petroleum sources have promoted some studies to empowerment of natural resources such as natural fibres for substituting or at least modifying petro-polymers. Because of biodegradability obtained from natural source, sorghum fibers are interesting to be used as filler in PP composites, despite of weak compatibility between them. Surface modification on the sorghum fibers through alkalinization prior to acetylation was aimed to improve the fiber compatibility to PP. The treatments were expected to substitute hydroxyl group in the sorghum fibers, into acetic ester group in order to increase their hydrophobicity as the fillers. Moreover, the treatments were able to unbundle single fibers into micro-fibrillated cellulose (MFC) fibres with increase in crystallinity index. Usage of this MFC fiber as filler in PP leads to improvement of the composite performances such as thermal properties. In this study, Fourier Transformation Infra-Red (FTIR) Spectroscopy, X-ray Diffraction (XRD), Differential Scanning Calorimetry (DSC) and Field-Emission Scanning Electron Microscope (FE-SEM) were used to evaluate the performances of the Sorghum fibers after the treatments and as the filler in the Sorghum fibers/PP composites. The experimental results showed the MFC fibers as the smallest sizes in 5.0 microns and the highest crystallinity index up to 79.1 %, obtained from alkalinization with 2.5 M NaOH prior to acetylation with 17.4 M CH3COOH and the glacial (CH3CO2)2. Compatibility study of the treated Sorghum fibers on PP shows an improvement indicated by a strong interaction between the fibers and PP on morphology observation, increase in melting point of PP from 163.4°C (using virgin Shorgum fibers) into 163.6°C (using treated Sorghum fibers) in DSC measurements.