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An introduction to the topic of aqueous silicone resin coating systems for exterior masonry. Concentrates on applications in the construction industry.

The purpose of this study was to fabricate silicone products that had different hardnesses and moduli, thus partially addressing the limitations of homogeneous materials whose deformation depends on altered structure or dimensions, and to provide new dimensions for the design of silicone soft structures.

A soft material three-dimensional printing platform with a dual-channel printing capability was designed and built. Using the material extrusion method, material screening was first performed using single-channel printing, followed by dual-channel-regulated printing experiments on products having different hardness and modulus values.

The proportion of additives has an effect on the accuracy of the printed product. Material screening revealed that Sylgard 527 and SE 1700 could be printed without additives. The hardness and mechanical properties of products are related to the percentage in their composition of hard and soft materials. The hardness of the products could be adjusted from 26A to 42A and the Young’s modulus from 0.875 to 2.378 Mpa.

Existing silicone products molded by casting or printing are mostly composed of a single material, whose uniform hardness and modulus cannot meet the demand for differentiated deformation in the structure. The existing multihardness silicone material printing method has the problems of long material mixing time and slow hardness switching and complicated multi-extrusion head switching. In this study, a simple, low-cost and responsive material extrusion-based hardness programmable preparation method for silicone materials is proposed.

The purpose of this paper is to study the ablative behavior of the silicone resin-coated carbon fabric (coated fabric) that will swell significantly during ablation.

The ablation experiments of three coated fabrics were conducted by quartz lamp radiant. Based on the experimental analysis, a numerical model was proposed for the coated fabrics to study the ablative process in term of the energy balance, mass conservation and thermal decomposition equations.

Results showed that the average relative errors between the simulated temperatures and experimental values of back surfaces of coated fabric 1, 2 and 3 were 10.01, 7.53 and 7.32%, respectively. The average density of silicone resin of coated fabric 1 was reduced by 47.96%, and the closer the distance from the heated surface was, the more the density decreased. The thermal conductivity and specific heat capacity of silicone resin of coated fabric 1 increased with time. Before 50 s, each decomposition rate curve showed an inflection point, at which the silicone resin decomposed most intensely.

Based on experimental observations, the ablative behavior of the material with fixed expansion layer was simulated. In the further research, the moving expansion layer could be considered.

This paper provides the theoretical basis to evaluate the effectiveness of thermal protection materials that will swell during ablation.

The extension of the vacuum-assisted multipoint moulding (VAMM) technology to a broader field of geometries makes it necessary to extend it with attachments to the enhanced vacuum-assisted multipoint moulding with additive attachments (EMMA) technology. Therefore, it is necessary to build additive manufactured attachments on a curved silicone surface by fused filament fabrication (FFF). The main challenge of FFF on a silicone-made build plate is the adhesion of the part on the build plate. Hence, the purpose of this paper is to find suitable and reliably manufacturable material and adhesion promoter combinations for the use of the FFF on silicone build plates.

The combinations of seven different filaments and four adhesion promoters were investigated with an experimental study. Therefore, four different specimen geometries were built with the different combinations and tested in a tensile test, and some of the specimens were analysed with a confocal laser scanning microscope (CLSM).

This study proves that the FFF on unheated silicone building plates is possible for several material combinations. As a filament material, polylactide can reliably be manufactured with all of the investigated adhesion promoters on the silicone build plate. Thereby, the highest adhesion strengths were achieved with an adhesive foil as an adhesion promoter, whereas the glue stick is the most appropriate solution. The investigations with the CLSM showed that there are large differences in the manifestation of the first layer depending on the adhesion promoter used.

To the best of the authors’ knowledge, this study is the first to demonstrate the manufacturing of FFF-made attachments on silicone build plates for the EMMA process. This paper provides measurement data on the build plate adhesion of the attachments on silicone-made build plates.

In this dichotomous study, the silicone-based softeners were produced with the contribution of some additives such as glycerin, polyethylene glycol 400 (PEG 400) and polyethylene glycol 4000 (PEG 4000) which had hydrophilic hydroxyl groups for providing or developing the hydrophilic character, lubricity and filling properties of the emulsions. The paper aims to discuss this issue.

The produced softeners were applied to the 100 percent cotton-knitted fabrics at different concentrations (owf%). In the first part of the study, the produced silicone emulsions were characterized via particle size, polydispersity index (PDI), zeta potential and TGA analyses. In addition, the effects of these emulsions on the mechanical properties of the fabrics were examined by bursting strength and pilling tests, and also the whiteness degrees (Berger value) of fabrics were researched. In the second part of the study, the effects of produced silicone softeners on the comfort properties of the fabrics were investigated.

According to the results, it was possible to say that the additives could be successfully added to the silicone emulsions, and they did not have a crucial effect on the properties of the emulsions or the mechanical and whiteness properties of the fabrics.

In this study, the additives were used as single form in the softeners recipes; however, their dual or trio combinations and/or their different concentrations could be used in the softeners emulsions.

In order to enhance the hydrophilic character, the lubricity and filling properties of the silicone softeners, they could be produced by using appropriate additives.

The contribution of the additives to the recipes of the silicone softeners is a novel approach.

The purpose of this paper is to propose a defect detection method of silicone caps positional deviation on flexible printed circuit board (FPCB) of keyboard based on automatic optical inspection.

First, the center of silicone caps of target keyboard FPCB image was extracted as feature points for generating the feature image which is used for registration rigidly with the reference feature image generated from the CAD drawings. Then, a flexible image registration method based on the surrounding-control-center B-splines (SCCB) strategy was proposed, which could correct the flexible deformation of the image generated by FPCB substrate while keeping the pasting deviation information about silicone caps unchanged. Finally, on this basis, a nearest neighbor strategy was proposed to detect the positional deviation of silicone caps.

Experimental results show that the proposed method can effectively detect the positional deviation defect of silicone caps. The G-mean value of the proposed method is 0.941746, which is 0.3 higher compared to that of similar research.

This paper presents a method to detect positional deviation defect of silicone caps on keyboard FPCB. Different from the classic B-spline image registration method, the proposed SCCB method used the neighborhood information of the pixel to be registered selectively to calculate the displacement vector needed for its registration, which overcame the problem that the silicone cap pasting deviation information disappears with the correction of the flexible deformation of the image.

The purpose of this study is to determine required paint and silicone proportions, their mixing rate and duration to eliminate the pattern problems caused by the misuse of silicone polymers in hammertone paints. Results of the findings aim at preventing raw material, manufacturing time and labour losses in hammertone paint production.

A paint formulation produced commercially was used. The effects of silicone proportion and mixing rate and paint and pigment density on the pattern formation within the paints, to which the spray painting method was applied, were investigated. Brightness controls of the produced paints were done, and the effect of the additive polymer on brightness was investigated. Photographs of paints for each practice were taken.

The most suitable silicone proportion and mixing conditions for the silver grey paints, in which Al non-leafing pigments were used, were calculated as 0.034-0.036 g/kg-paint and 15 s at 200 rpm, respectively. It was observed that the increase in pigment density increased required silicone proportion for the desired pattern. It was determined that mixing rate and duration were very significant in pattern formation, and that silicone decomposed and the pattern was disrupted in long-continued mixings. In addition, excess silicone use disrupted the pattern and decreased the paint brightness.

This research was conducted for hammertone paints, which are industrial and self-patterned aluminium silvered decorative paints. The results can be used for hammertone paint production.

The results will enable manufacturers to produce hammertone paints more economically. Results can be used in the paint industry to produce such paint.

It is crucial to produce high-quality products using less raw materials in today’s industry, where the amount of raw materials is decreasing, and economical and reliable production is becoming increasingly important. When environmental impacts in the solvent-based paint industry are taken into consideration, paint production in shorter times is important for both workers’ and environmental health. As a result of this study, hammertone paints will be produced more economically by appropriate production conditions yet without any energy, raw material and time loss.

Techniques of extrude and cure additive manufacturing for thermally cured, high viscosity and medical-grade silicone are investigated by using a small ram extruder and a near-infrared (IR) laser. The purpose of this study is to evaluate the process parameter effects on the stiffness of the final products.

Process parameter effects on axial stiffness values and durometer are explored. Parameters such as extrusion layer height, laser speed, laser current, laser raster spacing and multiple laser passes were investigated and compared to traditional cast and cure methods. Dimensional changes were also recorded and compared.

Tensile and durometer tests show that certain curing parameters give tensile stress and durometers within 10 per cent of bulk material specifications at 200 per cent strain. Parameters that had the highest impact on tensile stress at 200 per cent strain were layer height (0.73 per cent) followed by laser power (0.69 per cent), and then laser raster spacing (0.45 per cent). Parameters that had the highest impact on durometer were laser power (1.00 per cent), followed by layer height, (0.34 per cent) and then laser raster speed (0.32 per cent). Three-dimensional printed samples had about 11.2 per cent more shrinkage than the bulk cast samples in the longest dimension.

This paper is one of the first that demonstrates near IR laser curing parameter effects on three-dimensional printed, commercial off-the-shelf, medical-grade and viscous silicone. The ability to cure very viscous thermosets locally enables interesting technologies such as wire encapsulation, high voltage actuators and drug delivery devices.

The purpose of this paper is to investigate the effects of silicone-based softeners, which were developed with different particle sizes (nano, micro, and macro) and chemical structures, on the performance of 100 percent cotton fabrics knitted with different type of yarn (ring, open-end, and compact).

In the study, the silicone emulsions having expected particle sizes were produced at laboratory conditions. The produced silicone emulsions were applied to knitted fabrics with both padding and exhaust methods at different concentrations. Some characterization tests (particle size and zeta potential) were applied to the silicone emulsions before the applications. After the applications, CIELab values, whiteness and color fastness, hyrophility, abrasion, pilling, bursting strength, and stiffness performances of the samples were tested. The changes of the investigated properties were also examined via ANOVA.

According to the results, it was found that the silicone applications caused the CIELab values, whiteness degree, hyrophility, pilling, bursting strength and stiffness performance of the fabrics to change depending on the particle sizes of the emulsions, the yarn type of the fabrics, the application type, and the concentration of the silicone emulsions. When the ANOVA results were examined, it was seen that the types of the yarn and the silicone emulsions were the most effective working parameters on the results.

Because no additives were added to the produced silicone emulsions, in the future research, they can be developed with the use of some additives. Thus, it can resolve some of the disadvantages of the silicone emulsions on the textiles.

While applying the silicone softeners to the knitted fabrics, the type of the yarn and the particle sizes of the emulsions must be determined according to each other, in order to obtain enough handle performance without causing negative change on the other important properties of the knitted fabrics.

When the studies regarding silicone softeners were investigated, it was found that there were no studies about the effect of the silicone softeners having different particle sizes on the physical and chemical structures of the knitted fabrics depending on the type of yarn and some working parameters such as concentration and type of the application.

Silicone softeners are widely used in the textile industry to improve the performance of textile products. The thermal characteristics and flammability of polyester fabrics can be influenced by these compounds, which need to be considered, as important issues of human safety. The purpose of this paper is to investigate the changes induced on the polyester fibre by silicone softener treatment using a pad/dry/cure method.

The fibres were first treated with nano‐ and microemulsion silicone softeners. The influence of the silicone emulsion type on thermal properties and flammability of the resultant samples were investigated by various analytical techniques, namely, the differential scanning calorimetry (DSC), thermal gravimetric analysis (TGA), dynamical mechanical thermal analysis (DMTA) and horizontal flammability test (HFT).

Results showed that the silicone softeners increase the thermal degradation and flammability of the polyethylene terephthalate (PET) substrate.

The paper's study of thermal and flammability of the silicone‐treated sample is novel and can be used to optimize the properties of silicone polymers during production and consumption.