Pengaruh Variasi Rasio HAF/SRF Terhadap Sifat Vulkanisat NBR

The objectives of the research were to study the effect of HAF/SRF black ratio and the loading of sulfur on vulcanization characteristic, swelling behaviour and compression set of NBR vulcanizates. The ratio of HAF/SRF were 0/70; 10/60; 20/50; 30/40; 35/35; 40/30; 50/20 and 70/0 phr, respectively. The observation of this research consist of curing characteristic, morphology property and swelling equilibrium. Curing characteristic was determined from cure rate index (CRI), vulcanizates morphology was studied by SEM and swelling equilibrium was conducted by immersion test using benzene. The data were analyzed qualitatively to see the respond of the variable on physical properties. The curing characteristic of double filler vulcanizates was higher than those with single filler. Solvent uptake for double filler present in between to those with HAF or SRF. All of vulcanizates indicate the anomalous mass tranfer, with n>0,5 and constant k showed the same trend. The intrinsic diffusivity (D*), sorption and permeation coefficient showed similar trend and the maximum was obtained by the ratio HAF/SRF 0/70

Pengaruh variasi rasio HAF/SRF terhadap sifat vulkanisat NBR

ABSTRACTThe objectives of the research were to study the effect of HAF/SRF black ratio and the loading of sulfur on vulcanization characteristic, swelling behaviour and compression set of NBR vulcanizates. The ratio of HAF/SRF were 0/70; 10/60; 20/50; 30/40; 35/35; 40/30; 50/20 and 70/0 phr, respectively. The observation of this research consist of curing characteristic, morphology property and swelling equilibrium. Curing characteristic was determined from cure rate index (CRI), vulcanizates morphology was studied by SEM and swelling equilibrium was conducted by immersion test using benzene. The data were analyzed qualitatively to see the respond of the variable on physical properties. The curing characteristic of double filler vulcanizates was higher than those with single filler. Solvent uptake for double filler present in between to those with HAF or SRF. All of vulcanizates indicate the anomalous mass tranfer, with n>0,5 and constant k showed the same trend. The intrinsic diffusivity (D*), sorption and permeation coefficient showed similar trend and the maximum was obtained by the ratio HAF/SRF 0/70.ABSTRAKTujuan penelitian adalah mempelajari pengaruh rasio HAF/SRF terhadap karakteristik vulkanisat, kesetimbangan swelling dan perpindahan massa pada vulkanisat NBR. Rasio HAF/SRF yang digunakan berturut – turut 0/70; 10/60; 20/50; 30/40; 35/35; 40/30; 50/20 dan 70/0 phr. Pengamatan dilakukan pada karakteristik vulkanisasi, sifat morfologi dan kesetimbangan swelling. Data dianalisa secara kualitatif untuk melihat respon variabel penelitian terhadap sifat fisis vulkanisat. Karakteristik vulkanisasi ditentukan dari nilai indeks kecepatanvulkanisasi (cure rate index/CRI), morfologi vulkanisat dipelajari menggunakan alat SEM, dan kesetimbangan swelling dilakukan dengan cara perendaman dalam benzen dengan menghitung kecepatan penetrasi dan koefisien difusinya. Karakteristik vulkanisasi vulkanisat bahan pengisiganda memberikan nilai lebih tinggi daripada dengan bahan pengisi tunggal. Konsumsi pelarut (uptake) vulkanisat dengan bahan pengisi HAF dan SRF mempunyai nilai berada diantara vulkanisat dengan bahan pengisi tunggal. Mekanisme perpindahan massa untuk keseluruhan rasio HAF/SRF mengindikasikan anomali dengan nilai n>0,5 dan konstanta k yang relatif sama. Koefisien difusi intrinsik (D*), koefisien serapan (S) dan koefisien permeasi (P) secara umum menunjukkan kecenderungan dan nilai maksimum diberikan oleh rasio 0/70

PENGARUH FOTOKATALIS TITANIUM DIOKSIDA (Ti02) TIPE RUTIL DALAM REAKSI OZONISASI TERHADAP DEGRADASI FENOL

Penelitian yang dilakukan di laboratorium kimia FMIPA UNY ini beriujuan untuk menentukan pengaruh reaksi ozonisasi terhadap aktivitas degradasi fenol pada berbagai variasi waktu dan menentukan pengaruh fotokatalis titanium dioksida (Ti02) tipe rutil dalam reaksi ozonisasi terhadap aktivitas degradasi fenol pada berbagai variasi waktu. Subjek dalam penelitian ini adalah degradasi senyawa fenol, sedangkan objek dalam penelitian ini adalah aktivitas dari gas ozon (03) dan fotokatalis titanium dioksida (Ti02) tipe rutil. Percobaan ini dilakukan dalam 2 perlakuan, yakni degradasi fenol melalui reaksi ozonisasi dan degradasi fenol melalui reaksi ownisasi disertai penambahan fotokatalis titanium dioksida (Ti02) tipe rutil. Pada tiap perlakuan digunakan 6 sampel. Kemudian dilakukan perlakuan dengan variasi waktu 0 menit, 40 menit, 80 menit, 120 menit, 160 menit, dan 200 menit. Sampel tersebut kemudian disaring deugan corong buchner. Filtrat yang didapat diekstrak dengan kloroform. Sebelum diekstrak sampel diasamkan pada pH 2,1 dengan asam sulfat pekat. Setelah diekstrak, larutan dipisahkan dengan corong pisah kemudian dipekatkan. Hasil pemekatan dianalisis dengan alat kromatografi gas atau GC. Hasil penelitian menunjukkan baliwa semakin lama proses degradasi baik dengan reaksi ozonisasi maupun dengan fotokatalis titanium dioksida (Ti02) tiPe tutil, konsentrasi fenol semakin berkurang. Pada saat degradasi fenol melalui penggunaan reaksi ozonisasi, senyawa fenol terdegradasi secara lambat dengan harga k sebesar (1,6x10"3)/menit dan harga tl/2 sebesar 433,125 menit. Sedangkan degradasi fenol melalui reaksi ozonisasi disertai penambahan fotokatalis titanium dioksida (Ti02) tipe rutil, senyawa fenol terdegradasi cepat dengan harga k sebesar (3,6x10"3)/menit dan harga tl/2 sebesar 192,5 menit

The Optimization of Tunnel Type Biodigesters

The optimization of tunnel type digesters have been pursued by addition of commercial effective microorganism (EM4) and quick lime (CaO) in the digesters feed. Several variable have been observed to measure the performance of the digesters which are Chemical Oxygen Demand (COD) decrease between inlet and oulet slurry of digesters has also been measured to study the effect of digester feed modifications. The aim of this research is to improve the prerformance and ensure the effectiveness of tunnel type digester

Lactic Acid Production From Cocoa Pod Husk by Studying Further the Influence of Alkaloids on Fermentation Process using Lactobacillus Plantarum Bacteria

Cocoa Pod Husk (CPH) is the biomass waste from cocoa industry, generated after the digestion process. It accounts for about 70-75% of the cocoa fresh fruit. CPH contains active compounds of alkaloids that are thought to be the inhibitors of the lactic acid fermentation process using microorganisms. This study aims to produce Lactic Acid from CPH by studying further the influence of alkaloids on fermentation process using Lactobacillus plantarum bacteria. Fermentation using Lactobacillus plantarum bacteria was carried out at 50°C and with agitation at 100 rpm in incubator shaker for 48 h. This process was conducted to determine the effect of the addition of alkaloids by analyzing through the comparison between the consumption of substrate (glucose), dry weight of the cell, and the production of lactic acid. Evaluation of the differences in the performance of microorganisms at various treatments was performed based on the parameters values of the kinetic models prepared for the case studied. The kinetic model fitting results showed that the presence of alkaloids alters the growth patterns of products from growth-associated products into mixed patterns because the products were formed during slow growth and stationary phases. The maximum growth rate (μm) and substrate inhibition constant (Ks) obtained on each variation of inhibitor addition were likely to remain constant at the values of 0.69 h-1 and 3.89 g/L respectively, as these parameters were unaffected by the addition of inhibito

Mechanical properties and crystallinity of linear low density polyethylene based biocomposite film

Cassava starch filled linear low-density polyethylene (LLDPE) films are made in order to make plastics which environmentally friendly. The use of compatibilizer ethylene - acrylic ester - maleic anhydride polymerized is needed to obtain a compatible mixture of starch which is hydrophilic and LLDPE which is hydrophobic. In this study LLDPE films obtained were tested for tensile strength and elongation before and after accelerated aging and density. Melt flow index (MFI) of the film was also measured to determine the rheological properties. Crystallinity has been done by an X-Ray diffraction. The results showed that the addition of thermoplastic starch tended to reduce the tensile strength, elongation, and MFI values but increase the density of LLDPE films. The aging process at a temperature of 70°C ± 2°C for 168 hours ± 2 hours tends to increase the tensile strength but decrease the extension of the break

Mechanical Properties and Crystallinity of Linear Low Density Polyethylene Based Biocomposite Film

Cassava starch filled linear low-density polyethylene (LLDPE) films are made in order to make plastics which environmentally friendly. The use of compatibilizer ethylene - acrylic ester - maleic anhydride polymerized is needed to obtain a compatible mixture of starch which is hydrophilic and LLDPE which is hydrophobic. In this study LLDPE films obtained were tested for tensile strength and elongation before and after accelerated aging and density. Melt flow index (MFI) of the film was also measured to determine the rheological properties. Crystallinity has been done by an X-Ray diffraction. The results showed that the addition of thermoplastic starch tended to reduce the tensile strength, elongation, and MFI values but increase the density of LLDPE films. The aging process at a temperature of 70°C ± 2°C for 168 hours ± 2 hours tends to increase the tensile strength but decrease the extension of the break