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Analysis of Voids and Porosity and Its Influence on The Quality of Syntactic Foam Composites Munawar, Maulana Dzaki; Hakim, Moh Luqman; Wijaya, Ade Mundari; Novriadi, Dwi
Sainteknol : Jurnal Sains dan Teknologi Vol 21, No 2 (2023): December 2023
Publisher : Universitas Negeri Semarang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15294/sainteknol.v21i2.49530

Abstract

The syntactic foam composite possesses both light and strong qualities. Syntactic foam composite is commonly employed as a buoyant lighting material in amphibious aircraft due to its excellent foaming capability. Composite syntactic foam is utilized because of its ability to efficiently support material drying while maintaining excellent structural strength (mechanical characteristics). In order to ascertain the syntactic compound density, one can determine the composite density based on the ASTM D790 standard. This involves evaluating the porosity calculation and doing a literature review to establish the characteristics of the void. The density of a syntactic foam composite is determined by the density of the filling matrix (microballoon k15), the percentage of porosity, and the identification of voids. The use of the K15 microballoon material will reduce the overall density of the composite because of its substantial structure. The number of small cavities within the composite syntactic foam is indicated by the porosity ratio.Nevertheless, not all apertures present in syntactic foam composites can be classified as k15 microballoon structures, as the composite manufacturing process may result in the formation of air bubbles that become trapped within the composite. The function has no return value. The excessive presence of voids can significantly reduce the density and mechanical strength, leading to a drop in the overall quality of the syntactic foam composite. Porosity analysis is crucial for assessing the quality of drying in syntactic foam composites. The study involved assessing the composite density of syntactic foam with varying concentrations of 0-50% w/w of the k15 microballoon material, following the ASTM D790 standard. The porosity value of the foam was subsequently determined and studied. The findings of this study can serve as a robust point of reference for analyzing the correlation between the density of the reference material and the composite syntactical foam's relative density in different variations.
Effects of UV Exposure on the Physical, Chemical, and Mechanical Properties of Silica Microballoon Reinforced Epoxy Composites Yunus, Muhammad; Ardhyananta, Hosta; Hidayat, Mas Irfan Purbawanto; Rosidah, Afira Ainur; Laksmono, Joddy Arya; Jayatin, Jayatin; Susanti, Diah; Wijaya, Ade Mundari
Journal of Mechanical Engineering, Science, and Innovation Vol 4, No 1 (2024): (April)
Publisher : Mechanical Engineering Department - Institut Teknologi Adhi Tama Surabaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.31284/j.jmesi.2024.v4i1.6159

Abstract

Epoxy-based composites are widely used in various applications due to their excellent mechanical properties and durability, but their performance under prolonged UV exposure remains a critical concern. This study examines the impact of UV exposure on the physical, chemical, and mechanical properties of epoxy-silica microballoon composites over curing periods of 0, 200, and 400 hours. Results indicate that UV treatment increased the density from 1.0073 g/cm³ to 1.0129 g/cm³. SEM images showed a reduction in fragmentation of epoxy microballoons, indicating stronger bonding. EDX results revealed some changes in elemental composition, with a notable decrease in the percentage of sodium from 0.81 wt.% to 0.18 wt.% and silicon from 7.16 wt.% to 0.12 wt.%. FTIR analysis identified a new hydrogen bond formations at 3350 cm⁻¹. Mechanical testing showed that UV treatment significantly increased the flexural stress from 36.83 MPa to 49.98 MPa. Additionally, hardness (Shore D) increased from 78.4 to 80.2 Shore D. These findings highlighted the significant effects of UV exposure on the structural integrity and bonding mechanisms of the composites, offering valuable insights for their use in UV-prone environments.
Cold Plasma-Induced Surface Modification of Microfibrillated Cellulose Using Lauric Acid to Enhance Compatibility in Polymer Composites Rifathin, Annisa; Wijaya, Ade Mundari; Roziafanto, Achmad Nandang; Laksmono, Joddy Arya; Nugraha, Adam Febriyanto; Chalid, Mochamad
Indonesian Journal of Chemistry Vol 25, No 4 (2025)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/ijc.104738

Abstract

Green materials, such as microfibrillated cellulose (MFC), are increasingly used as fillers in polymer composites for academic and industrial applications. However, their inherent hydrophilic property limits compatibility with polymer matrix. This study employs an environmentally friendly cold plasma technique to modify the surface of MFC, improving its compatibility with the polymer. Plasma treatment was performed at a voltage of 60 V for 30 min by making three molar ratios (3:1, 4:1, and 5:1) between lauric acid as a hydrophobic precursor and anhydroglucose (AGU). The results indicate several changes in the modified MFC properties, as evidenced by the appearance of a new peak at a wavenumber of 1742 cm−1 (ester’s C=O) in FTIR spectra, indicating successful plasma-induced grafting. XPS results also confirm the formation of O–C=O bond at a binding energy of 289.3 eV. The optimum conditions were obtained at a molar ratio of 4:1 (lauric acid:AGU). There was a decrease in the hydrophilic property of MFC, indicated by an increase in the water contact angle from 50.16° to 71.26°. Moreover, the surface tension difference between MFC and polypropylene was significantly reduced from 136.99 to 47.51%, suggesting improved compatibility.