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Untuk memperluas penggunaan kayu lapis meranti putih maka dilaksanakanlah penelitian terhadap perekat urea formaldehida yang dimodifikasi dengan melamin dengan formulasi tertentu. Mengingat sifat formaldehida yang dengan mudah dapat berpolimerisasi maka peranan dari metanol sebagai penghambat di dalam larutan formaldehida sangat penting.

Kadar metanol yang bervariasi (2% - 10%) ditambahkan pada proses sintesa urea melamin formaldehida. Kualitas hasil sintesa kemudian dibandingkan terhadap standar mutu JIS. Pengujian yang berkaitan dengan aplikasi yang dilakukan adalah kuat rekat pada keadaan normal dan keadaan setelah perendaman air panas mengingat keunggulan yang dimiliki perekat UMF adalah sifat ketahanan terhadap air.

Hasil yang diperoleh menunjukkan bahwa penambahan metanol di dalam formalin menghasilkan UMF yang dapat memberikan kuat rekat kayu lapis meranti putih rata-rata 45 kg/cm2 pada keadaan normal. Kenaikan kadar methanol sampai 10% tidak berpengaruh secara linear terhadap kuat rekat pada keadaan normal. Namun dapat diperoleh suotu kenaikan kuat rekat bila dibandingkan terhadap standar. Sedangkan untuk keadaan setelah perendaman dalam air, terjadi pula kenaikan dalam kuat rekat bila dibandingkan terhadap standar tetapi hasil yang diperoleh berfluktuasi.

Diduga proses perendaman yang disertai pemanasan dapat lebih menyempurnakan reasi cure dari resin UMF. Sifat kayu yang anisotropi besar kemungkinan menjadi penyebab terjadinya fluktuasi nilai kuat rekat yang diper oleh.

Ikatan antar 2 (dua) permukaan venir meranti putih dengan perekat urea melamin formaldehida merupakan kejadian yang sangat kompleks. Kuat rekat yang dihasilkan bergantung pada beberapa kondisi yang mempengaruhinya termasuk : sifat perekat, sifat kayu, formulasi kompon perekat, preparasi venir, karakteristik kandisi aperasinya atau sifat pengerjaan dan ketepatan perlakuan pengujian yang sesual dengan aplikasinya.

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Telah dilakukan penelitian pengaruh jenis inisiator, jenis surfaktan dan waktu feeding monomer dari kopolimer Butil akrilat-Asam metakrilat terhadap kinerja pressure sensitive adhesives berbasis air. Proses polimerisasi dilakukan menggunakan teknik seeding melalui polimerisasi radikal bebas pada temperatur reaksi 85±1 oC dengan kecepatan pengadukan 200 rpm.Tipe inisiator divariasi menggunakan APS dan KPS, surfaktan menggunakan LDBS dan SLS serta waktu feeding dibuat 2, 3 dan 4 jam. Parameter polimer PSA seperti : total padatan, viskositas, pH, tegangan permukaan, ukuran partikel, tack, shear dan adhesion diuji. Variasi inisiator, surfaktan dan waktu feeding tidak mempengaruhi total padatan, viskositas, pH dan tegangan permukaan polimer PSA. Efek variasi inisiator, surfaktan dan waktu feeding monomer mempengaruhi ukuran dan distribusi ukuran partikel dimana ukuran partikel paling kecil diperoleh dari kombinasi antara inisiator KPS, surfaktan SLS dan waktu feeding 3 jam. Sedangkan kinerja secara keseluruhan dari polimer PSA didapat dari kombinasi antara inisiator APS, surfaktan LDBS dan waktu feeding 2 jam dengan parameter tack : 4 cm, shear : 18 menit dan adhesion : 6,56 N

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A research has been conducted to investigate the effect of various initiator, surfactant and feeding time of Buthyl acrylate-Methacrylic acid copolymer on the performance of water based pressure sensitive adhesives. Polymerization was done by seeding technique through free radical polymerization at the reaction temperature 85±1 oC and the speed of agitation 200 rpm. Initiator was varied by using Ammonium persulfate and Potassium persulfate, surfactant using LDBS and SLS then feeding time was made in 2, 3 and 4 hours. The parameter of PSA polymer i.e solid content, viscosity, pH, surface tension, particle size, tack, shear and adhesion were tested. The variation of initiator, surfactant and feeding time did not effected solid content, viscosity, pH and surface tension of PSA polymer. Variation of initiator, surfactant and feeding time influenced particle size and distribution particle size where the smallest particle size were achieved by combination initiator Potassium persulfate, surfactant SLS and feeding time of monomer 3 hours. Overall, the performance of PSA polymer was achieved by combination initiator Ammonium persulfate, surfactant LDBS and feeding time of monomer 2 hours with parameters tack: 4 cm, shear: 18 minutes and adhesion: 6,56 N.

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Komposit sandwich merupakan salah satu material yang banyak digunakan sebagai material penyusun rancang bangun struktur ringan karena memiliki perbandingan strength to weight yang tinggi. Penelitian ini bertujuan untuk membandingkan sifat mekanik komposit sandwich dengan kulit epoksi berpenguat woven roving glass fiber dan inti honeycomb polypropylene dengan metode fabrikasi cold press-adhesive dan Vacuum Assisted Resin Infusion (VARI). Uji tekan, uji tarik, serta uji lentur dilakukan untuk mengetahui kekuatan mekanik, pengamatan morfologi komposit sandwich sebelum dan sesudah pengujian dilakukan untuk mengetahui kerusakan material komposit sandwich tersebut. Hasil penelitian ini menunjukkan komposit sandwich metode VARI memiliki sifat mekanik yang lebih baik dibandingkan komposit sandwich metode cold press-adhesive, yaitu memiliki kuat tekan, kuat tarik, dan kuat lentur secara berurutan sebesar (2,21 ± 0,02) MPa, (0,36 ± 0,04) MPa, dan (26,87 ± 0,30) MPa. ......Sandwich composite is one of the materials that has been widely used as a material for lightweight structures because it has a high strength-to-weight ratio. Sandwich composites with woven roving glass fiber reinforced epoxy skin and honeycomb polypropylene core and their mechanical properties was studied. This research aimed to compare mechanical properties of sandwich composites woven roving glass fiber reinforced epoxy skin and honeycomb polypropylene core with cold press-adhesive and Vacuum Assisted Resin Infusion (VARI) fabrication methods. Compression, tensile, and flexural tests were carried out to determine the mechanical strengths, while morphological observations of the sandwich composites before and after the tests were observed to determine the failures. The results showed that the sandwich composites fabricated by VARI method had better mechanical properties than ones by the cold press-adhesive method, with compressive, tensile, and flexural strength were (2.21 ± 0.02) MPa; (0.36 ± 0.04) MPa; and (26.87 ± 0.30) MPa, respectively.

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Single-step self-etch adhesive systems are the system that combine self etching primer and bonding agent into one step application. This system was developed as the effort to simplified in application prosedures and give a good bond strength of resin composites to dentin surface. The purpose of this study was to examine the bond strength of resin composites with two singlestep self-etch adhesives system (Xeno III and Clearfil Tri-S Bond) to bovine dentin at temperature of adhesive 3ºC, 22ºC and 30ºC. Adhesive was applied to dentin surface (bovine insisivus mandibular dentin) follow by resin composites bonded according to the manufacturer’s instructions. Tensile bond strength of 60 specimens were tested UTM (universal testing machine) after 24 hours storage in aquadest at 37 ºC. The results were analyzed using ANOVA test followed by Tukey’s test (p< 0,05). The bond strength of Xeno III was significantly diffrent from that of Clearfil tri-S Bond, 0,66±0,271, 2,70±1,528, 0,23±0,104 versus 2,07±0,272, 4,77±0,689, 4,39±1,205 MPa at temperature of materials 3ºC, 22ºC and 30ºC respectively. The bond strength of two single- step adhesives system (Xeno III and Clearfil Tri-S Bond) were highest at temperature 22ºC than other temperatures of materials.

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Structural adhesives have been widely used to join metal to metal, and metal to composite in automotive and aircraft structures. However, the adhesive is susceptible to water absorption from the surrounding environment and this affects the mechanical properties of the adhesive, leading to reduction in the performance of the structure. This paper investigated the water absorption and desorption behaviour of FM 73M structural adhesive film and its effect on the tensile properties. The adhesive was immersed in deionised water at a temperature of 50oC. A gravimetric method was carried out to obtain the water uptake. Dog bone specimens were used to investigate the residual tensile strength of the adhesive. Finite element modelling was performed to model the spatial moisture distribution in the adhesive and the residual tensile strength after having absorbed water. It was found that the water absorption of FM 73M deviated from Fick's second law, however the desorption behaviour followed Fick's second law. The tensile properties of the adhesive (the tensile strength and the elastic modulus) tend to decrease with the increase of water content and they are recovered after desorption at the same temperature as the absorption. The residual tensile strength was predicted using a continuum damage approach combined with environmental degradation. Good agreement has been found between the predicted and the experimental results.