scholarly journals EFFECT OF SODIUM THIOSULFATE ON BOND STRENGTH OF AN EPOXY RESIN–BASED SEALER TO SODIUM HYPOCHLORIDE- AND CITRIC ACID-TREATED DENTIN

Author(s):  
Ezgi Doğanay Yıldız ◽  
Hakan Arslan ◽  
Mine Özdemir ◽  
İsmail Uzun ◽  
Ertuğrul Karataş ◽  
...  
Coatings ◽  
2019 ◽  
Vol 9 (11) ◽  
pp. 757 ◽  
Author(s):  
Kim ◽  
Hong ◽  
Han ◽  
Kim

In this study, coating equipment for the effective underwater repair of submerged structures was developed. The tensile bond characteristics of selected epoxy resin coatings were investigated by coating the surface of a specimen using each of the four types of equipment. Using the experimental results, the tensile bond strength and the coating thickness were analyzed according to the type of equipment, coating, and curing time. The results show that the type of coating equipment used had the greatest effect on the measured bond strength and coating thickness of the selected coatings. However, the effect of coating type and curing time on the bond strength and the thickness was observed to be insignificant. Compared with the developed equipment, the surface treatment of the coating was observed to be more effective when using the pre-existing equipment, and thus the bond performance of the coating was improved compared to using the pre-existing equipment. Based on the experimental results, improvements and needs involving the equipment for further research were discussed.


2016 ◽  
Vol 16 (1) ◽  
Author(s):  
Fatih Cakici ◽  
Elif Bahar Cakici ◽  
Kadir Tolga Ceyhanli ◽  
Ersan Celik ◽  
Funda Fundaoglu Kucukekenci ◽  
...  

2012 ◽  
Vol 28 ◽  
pp. e5-e6
Author(s):  
A.C.P. Corrêa ◽  
A.A. Zaia ◽  
B.P.F.A. Gomes ◽  
F.J. Souza-Filho ◽  
J.F. Almeida ◽  
...  

2020 ◽  
Vol 14 (1) ◽  
pp. 84
Author(s):  
Ragil Widyorini ◽  
Ikhwan Syahri ◽  
Greitta Kusuma Dewi

Bambu memiliki kandungan ekstraktif dengan persentase yang berbeda antar jenis bambu. Penelitian ini bertujuan untuk mengetahui pengaruh perlakuan ekstraksi pada jenis bambu yang berbeda terhadap sifat papan partikel. Dua jenis bambu digunakan yaitu Bambu Petung (Dendrocalamus asper) dan Bambu Wulung (Gigantochloa atroviolacea). Perlakuan ekstraksi digunakan pada partikel bambu sebelum proses pembuatan papan partikel yaitu tanpa ekstraksi, ekstraksi air dingin dan ekstraksi air panas. Papan partikel dibuat dalam ukuran 25 cm x 25 cm x 0,7 cm, target kerapatan 0,9 g/cm3, jumlah asam sitrat 30%, serta kondisi pengempaan suhu 180°C selama 10 menit. Hasil penelitian menunjukkan bahwa interaksi perlakuan ekstraksi dan jenis bambu hanya berpengaruh signifikan pada sifat penyerapan air dan keteguhan rekat internal, sedangkan jenis bambu berpengaruh signifikan pada nilai kadar air, modulus patah dan modulus elastisitas. Semua papan partikel yang dihasilkan memenuhi standar Japanese Industrial Standard (JIS) A 5908 tipe 13. Pada penelitian ini, papan partikel dari bambu wulung tanpa perlakuan ekstraksi mempunyai nilai yang memenuhi standar tipe 18 dan berpotensi sebagai bahan baku untuk produk furnitur eksterior. Perlakuan ekstraksi dapat meningkatkan secara signifikan nilai keteguhan rekat internal papan partikel bambu petung, walaupun secara umum dengan jumlah asam sitrat 30% perlakuan tersebut tidak diperlukan pada papan partikel bambu Properties of Particleboard made from Petung Bamboo (Dendrocalamus asper) and Wulung Bamboo (Gigantochloa atroviolacea) Particles with Extraction TreatmentAbstractBamboo has extractives, which the percentage of extractive was different based on bamboo species. This research aimed to investigate the effect of extraction treatment at different bamboo species on the particleboard properties. Two types of bamboo were used, i.e. Petung bamboo (Dendrocalamus asper) and Wulung bamboo (Gigantochloa atroviolacea). Three extraction treatments were conducted to the bamboo particles before the particleboard manufacture, i.e. unextracted, cold-water extraction, and hot-waterextraction. The particleboard was made in the size of 25 cm x 25 cm x 0.7 cm, target density of 0.9 g/cm³, citric acid content of 30%, and pressing temperature of 180°C for 10 min. The results showed that the interaction between extraction treatment and bamboo species significantly affected on the water absorption and internal bond strength, however bamboo species affected significantly on the moisture content, modulus of rupture, and modulus of elasticity. All of particleboards could met the requirement of the 13 type of Japanese Industrial Standard (JIS) A 5908. In this research, particleboards made from wulung bamboo particles without extraction treatment have properties that met the requirement of the 18 type and the products have potential to be as exterior materials for furniture. In general, an extraction treatment was not an important step on the manufacturing of bamboo particleboard using citric acid 30% as adhesive. However, the extraction treatment could increase significantly the internal bond strength of particleboard made from petung bamboo.


2011 ◽  
Vol 82 (1) ◽  
pp. 30-35
Author(s):  
Shinya Horiuchi ◽  
Shingo Kuroda ◽  
Masahiro Hiasa ◽  
Toshiyuki Suge ◽  
Seitaro Saku ◽  
...  

Abstract Objective: To determine the reinforcement of bond strength of a self-etching system by applying a pretreatment agent. Materials and Methods: Sixty extracted human premolars were used in this study. The enamel surfaces were treated with four pretreatment agents—phosphoric acid, polyacrylic acid, citric acid, and ammonium hexafluorosilicate (SiF)—and were examined under a scanning electron microscope. Afterward, orthodontic brackets were bonded with a self-etching adhesive system (n  =  10 for each agent), and shear bond strength was measured through a debonding process. The adhesive remnant index (ARI) was also assessed. Results: Enamel surfaces treated with polyacrylic acid seemed almost the same as intact enamel. Treatment with SiF induced slight shallow depressions compared with the intact enamel. On the other hand, enamel surfaces treated with citric acid and phosphoric acid showed severe etching patterns. All pretreatments increased the bond strength, but SiF-treated specimens revealed the greatest strength (12.201 ± 1.048 MPa), followed by polyacrylic acid (12.030 ± 2.103 MPa). The control group with no pretreatment showed the least strength (9.078 ± 1.678 MPa). All pretreatments increased ARI score compared with the control group. Conclusions: Surface conditioning before bracket adhesion could reinforce the bond strength of the self-etching adhesive system, resulting in a more reliable bonding system.


Coatings ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 1159
Author(s):  
Sungwon Kim ◽  
Hyemin Hong ◽  
Jun Kil Park ◽  
Sangmin Park ◽  
Seoung Ik Choi ◽  
...  

This study aims to investigate the effects of different exposure conditions on the interfacial bond between steel plates and epoxy resin coatings at early ages. Test variables include the epoxy resin types, exposure conditions, exposure periods, and coating equipment. The selected epoxy resins were applied to prepared steel plates and cured at each exposure condition for 7, 28, 56, or 91 days, and the pull-off bond strength and coating thickness were measured. Scanning electron microscopy (SEM) images were obtained to study the interfacial bond for some representative coatings. Three different exposure conditions (indoors and actual marine environment) were considered in this study. This study is also focusing on the improvement of previously developed underwater coating equipment and evaluating the performance. Experiments were conducted to evaluate the performance of the improved equipment types under different environmental conditions: indoors (tap water and seawater) and outdoor conditions. The improved equipment types were confirmed to be effective for underwater coating and easier to use than the previous equipment under real sea conditions. The experimental results also confirmed that the bond strength of the coating decreased as the curing time increased.


2020 ◽  
Vol 10 (7) ◽  
pp. 2535
Author(s):  
Hyoung-Sik Kim ◽  
Song-Yi Yang ◽  
Eun Ha Choi ◽  
Kwang-Mahn Kim ◽  
Jae-Sung Kwon

The purpose of the study was to evaluate the adhesion between dental core resin and epoxy resin-based fiber post after treatment with non-thermal atmospheric pressure plasma (NTAPP) and compare with conventional methods of epoxy resin-based fiber post treatments. Contact angle was measured on the surface of epoxy resin before and after NTAPP treatment and X-ray photoelectron spectroscopy was used to analyze the surface chemistry. Finally, two shear bond strength tests were carried out; shear bond strength between core resin and epoxy resin for comparison between NTAPP treated and untreated sample, and push-out shear bond strength between core resin and NTAPP treated commercially available epoxy resin-based fiber post for comparison between NTAPP treated samples with conventionally treated samples. Contact angle on the surface of epoxy resin generally decreased with increasing NTAPP treatment time with presence of surface chemical changes. Also, there was significantly higher shear bond strength and push-out shear bond strength between epoxy resin and core resin for NTAPP treated epoxy resin, even to the conventionally treated epoxy resin-based fiber post with hydrofluoric acid or silane. In conclusion, new technology of NTAPP has potential for application on the epoxy resin-based fiber post to improve endodontic restoration success rate.


2014 ◽  
Vol 30 ◽  
pp. e60
Author(s):  
M.D. Sousa-Neto ◽  
M. Brito-Júnior ◽  
G.B. Leoni ◽  
R.D. Pereira ◽  
J.F.M. Chaves ◽  
...  
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