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"Skripsi ini dilaksanakan untuk melakukan perbaikan proses produksi material komposit khususnya untuk komponen kendaraan bennotor yang umumnya diproduksi dengan metode konvensional yang dikenal dengan teknik lay up.Dari pengalaman selama ini teknik Lay up masih banyak digunakan karena prosesnya yang sangat mudah, namun demikian produk yang dihasilkan memiliki banyak kekurangan seperti, kekuatan komposit yang rendah, kepresisian dimensi produk yang rendah, ketidakefisienan dalam penggunaan material maupnn proses finishing produk akhir.Berdasarkan pengamatan tersebut, tulisan ini mengembangkan teknik produksi material komposit dengan mengembangkan teknik Resin Injection Molding atau Resin Transfer Molding. Teknik ini membutuhkan perlengkapan khusus yaitu cetakan tertutup, yaitu cetakan yang terdiri atas dua cetakan atas dan bawah dan pompa injeksi yang digunakan menginjeksikan resin.Dengan teknik ini dapat dihasilkan produk dengan kekuatan yang lebih baik, kepresisian bentuk yang baik, daur produksi yang lebih tinggi dan tingkat efisiensi yang lebih tinggi dalam penggunaan bahan baku material.Pengembangan yang dilakukan dalam tulisan ditujukan pada penyederhanaan baik peralatan yang digunakan maupun proses kerjanya sehingga peralatannya menjadi lebih sederhana dan dapat dibuat dengan murah.

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A day using composite material in engineering is more popularly. Even for simple constructional appliance people have applicated composite materials as alternative material non-metal. The one of is otomotive spesially in producing body construction for motor vehincle as motorcycle or motorcar.

At present people still apply conventional metode in producing structural composite known as hand lay up metode. The metode is still using because it?s easy process. But the product is produced by this metode has many shortages such as low composite power, bad dimensional and low precision product un eiiicient in using material or time for finishing process.

By the research, this writing develops productional tehcnic of composite material with developing Resin Injection Molding technio or Resin Transfer Molding. This technic needs special material that is locked which has Female and male mold and injection pump that used to pump resin.

The development in the case has been done in writing intended for simplification to material that used and material maker or the work process so the material become more simple and can be produced cheaper."

"Latar Belakang : Studi ini mengevaluasi sifat mekanik kekuatan tekan dan sifat fisik morfologi permukaan Resin Komposit Bulk-fill Packable dengan Flowable. Kedua material ini memiliki kemampuan berpenetrasi cahaya hingga kedalaman 4 mm namun dengan viskositas yang berbeda. Keduanya memiliki kandungan monomer dan konsentrasi filler yang berbeda dimana hal tersebut mempengaruhi sifat mekanik dan fisiknya. Tujuan : Mengetahui perbandingan kekuatan tekan Resin Komposit Bulk-fill Packable dengan Flowable, serta hubungannya dengan morfologi permukaan. Metode : 12 spesimen Resin Komposit Bulk-fill Packable dan Flowable disiapkan untuk uji kekuatan tekan lalu dianalisis dengan uji Independent T-test. Kemudian spesimen Resin Komposit Bulk-fill Packable dan Flowable disiapkan untuk analisis morfologi permukaan menggunakan SEM. Hasil Penelitian : Tidak terdapat perbedaan bermakna nilai kekuatan tekan antara Resin Komposit Bulk-fill Packable dan Flowable dengan nilai kekuatan tekan RK Bulk-fill Packable lebih tinggi dibandingkan dengan Flowable. Resin Komposit Bulk-fill Packable memiliki permukaan eksternal yang lebih tidak beraturan, ukuran partikel yang beragam, dan lebih banyak porus. Kesimpulan : Resin Komposit Bulk-fill Packable menunjukkan nilai kekuatan tekan yang sama dengan Resin Komposit Bulk-fill Flowable. Material RK Bulk-fill Packable memiliki morfologi permukaan yang tidak beraturan, lebih banyak porus, dan ukuran partikel yang lebih beragam dibandingkan dengan RK Bulk-fill Flowable.

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Background : This study evaluates the compressive strength and surface morphology of the Resin Composite Bulk-fill Packable and Flowable. Both of these materials have the ability to penetrate light to a depth of 4 mm but with different viscosities. Each Resin Composite Bulk-fill have different monomer content and filler concentrations which affect their mechanical and physical properties.

Objective : Knowing the comparison of the compressive strength of Resin Composite Bulk-fill Packable with Flowable, and its relationship with surface morphology. Methods : 12 specimens of Resin Composite Bulk-fill Packable and Flowable were prepared for compressive strength test and then analyzed by Independent T-test. Then specimens of Resin Composite Bulk-fill Packable and Flowable were prepared for surface morphology analysis using SEM.

Results : There was no significant difference in the compressive strength values between Resin Composite Bulk-fill Packable and Flowable with the compressive strength of Resin Composite Bulk-fill Packable being higher than Flowable. Resin Composite Bulk-fill Packable have a more irregular external surface, a variety of particle sizes, and are more porous.

Conclusion : Resin Composite Bulk-fill Packable shows the same compressive strength value as Resin Composite Bulk-fill Flowable. The Resin Composite Bulk-fill Packable material has an irregular surface morphology, more voids, and more diverse particle size compared to Resin Composite Bulk-fill Flowable."

"Penelitian ini bertujuan mengembangkan Alat Tekan Panas (Hot-Press) untuk Proses pembuatan komposit matriks berpenguat serat panjang/tekstil dengan termoset (Thermoset Composite). Hasil Penelitian menunjukkan faktor tekanan dan temperatur yang dipakai pada pada proses tersebut merupakan penentu kekuatan dan kualitas dari produk komposit. Penelitian ini, juga memulai kasus kajiannya untuk Biodegradable Composite yang dibangun dari unsur-unsur matriks alam (PLA- PolyLactic Acid) dan serta penguat serat alam Ramie. Dari hasil pengembangan dan pengujian alat, Alat Cetak Tekan Panas dapat berfungsi dengan baik dan menghasilkan mutu produk komposit serat alam yang jauh lebih baik dibanding hand-lay-up dan relatif cukup murah (Low-cost manufacturing process).

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This study aims to develop a Hot-Press for the manufacturing process of a long fiber / textile reinforced matrix composite using a thermoset (Thermoset Composite). The results showed that the pressure and temperature factors used in the process were determinants of the strength and quality of the composite product. This research also started its case study for Biodegradable Composite which is built from natural matrix elements (PLA-PolyLactic Acid) and also Ramie's natural fiber reinforcement. From the results of the development and testing of the tool, the Heat Press Printing Tool can function well and produce quality natural fiber composite products that are far better than hand-lay-up and relatively cheap (Low-cost manufacturing process)."

"Latar Belakang: Pengunyahan merupakan proses makanan dihancurkan dan dicampur dengan air liur untuk membentuk bolus untuk ditelan. Proses pengunyahan memberikan tekanan pada gigi yang mempengaruhi degradasi sifat mekanik pada gigi. Salah satu cara untuk mengembalikan email yang terdegradasi adalah dilakukan restorasi dengan bahan seperti resin komposit. Bahan restorasi diharapkan memiliki sifat mekanik yang sebanding dengan email. Tujuan: Menganalisis perbedaan kekerasan mikro permukaan resin komposit mikro hibrida dengan resin komposit nano hibrida. Metode: 8 spesimen resin komposit mikro hibrida (Kerr Herculite™ Précis Composite) dan 8 spesimen resin komposit nano hibrida (Kerr Harmonize™ Nano hibrida Universal Composite) disiapkan untuk uji kekerasan mikro permukaan lalu dianalisis dengan uji Independent T-Test. Hasil Penelitian: Terdapat perbedaan bermakna dengan signifikansi p<0,041 (p<0,05) antara nilai kekerasan mikro permukaan resin komposit mikro hibrida dan resin komposit nano hibrida dengan nilai kekerasan resin komposit nano hibrida lebih tinggi (45,51 KHN) dibandingkan dengan resin komposit mikro hibrida (42,31 KHN). Kesimpulan: Resin komposit nano hibrida memiliki kekerasan mikro permukaan lebih tinggi dibandingkan dengan resin komposit mikro hibrida.

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Background: Chewing is the process of crushing food and mixing with saliva to form a bolus for swallowing. The chewing process puts pressure on the teeth which affects the degradation of the mechanical properties of the teeth. One of the ways to restore degraded enamel is to do restoration with materials such as composite resin. The restoration material is expected to have mechanical properties comparable to that of enamel. Objective: Analyzing the differences in surface microhardness of microhybrid composite resin with nanohybrid composite resin. Methods: 8 specimens of microhybrid composite resin (Kerr Herculite ™ Précis Composite) and 8 specimens of nanohybrid composite resin (Kerr Harmonize ™ Nanohybrid Universal Composite) were prepared for surface microhardness testing and then analyzed by Independent T-Test. Result: There was a significant difference with a significance of p <0.041 (p <0.05) between the surface micro-hardness value of hybrid micro-composite resin and nano-hybrid composite resin with higher surface microhardness value for nanohybrid composite resin (45.51 KHN) compared to microhybrid composite resin. (42.31 KHN). Conclusion: The nanohybrid composite resin has higher surface microhardness compared to the microhybrid composite resin."

"The aim of this in vitro study was to evaluate the shear bond strength of resin composite materials to dentin by using different bonding agents. Forty human premolars were selected for the study, and cylindrical posts of either Spectrum TPH and Charisma were bonded vertically to a standard flat dentinal area, prepared on the buccal survace. A chisel-shaped shearing blade, attached to the crosshead of a universal mechanical testing machine. The shear bond strengths to dentin of 10 resin composite-dentin adhesive combinations were measured. The results showed that the bond strength values of dentin bonding agents were not significant (p>0.05). It seems important for clinicians to use the combination of resin composite and dentin bonding agent recommended by the manufacturer."

"TKKS merupakan limbah perkebunan kelapa sawit dengan kandungan serat selulosa yang dapat dimanfaatkan sebagai bahan penyusun komposit. Komposit serat alami dengan matriks epoksi dikenal memiliki resistansi kimia yang baik. Penambahan carbon nanotube pada komposit diketahui melalui banyak penelitian dapat meningkatkan sifat mekanik. Pada penelitian ini dilakukan penambahan carbon nanotube pada komposit serat TKKS dengan matriks epoksi sebanyak 0,1%, 0,5%, dan 1% dari berat matriks yang digunakan. Serat TKKS didapatkan dengan metode chemical retting. Untuk meningkatkan kompabilitas, fungsionalisasi dan perlakuan carbon nanotube dan serat TKKS dilakukan dengan metode mild acid oxidation dan silane coupling agent dan terbukti tidak merusak struktur dan ukuran carbon nanotube. Penambahan carbon nanotube meningkatkan kekuatan tarik komposit serat TKKS dengan matriks epoksi sebesar 10,03%, 4,75%, dan 7,75% dan kekuatan tekuk sebesar 51,64%, 65,8%, dan 105,9% masing-masing untuk penambahan carbon nanotube sebanyak 0,1%, 0,5%, dan 1% dari berat matriks yang digunakan.

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Empty palm oil fruit bunch fiber is the side product of palm oil cultivication that contain cellulose fiber. This kind of fiber is usually used as composite reinforcement. Natural fiber reinforced composite with epoxy matrices well known of its chemical stability. Addition of carbon nanotube also known to strengthen epoxy based composites. In this research, carbon nanotube is added as much as 0,1%, 0,5%, and 1% wt in matrices. The empty palm oil fruit bunch fiber is prepared by chemical retting process.

Functionalization and surface treatment of carbon nanotube and natural fiber with mild acid method and silane coupling agent are performed in order to increase the compatibility. It was proved by FE-SEM that no damage was occurred to the carbon nanotube. The addition of carbon nanotube has increased the tensile strength as much as 10.03%, 4.75%, and 7.75% and flexural strength as much as 51.64%, 65.8%, dan 105.9% each for addition of 0.1%, 0.5%, and 1% weight carbon nanotube."

"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."