Fourrier Transform Infrared Research Articles

Engineering fully quaternized (Dimethylamino)ethyl methacrylate-based photoresins for 3D printing of biodegradable antimicrobial polymers

Nowadays, medical devices or implants are widely used in the medical field to treat different diseases. However, bacterial infections are one of the significant problems associated with medical devices and are recognized as a concern in healthcare worldwide. Addressing this problem has driven the exploration of new materials with potent antibacterial properties. In this regard, quaternary ammonium compounds (QACs), which are organic salts with an alkane chain and a charged part of quaternary ammonium groups, came up with a potent antibacterial activity. Herein, we report for the first-time dimethylamino ethyl methacrylate (DMAEM) derived quaternary ammonium monomer and crosslinker to prepare photoresins for DLP (Digital light processing) 3D printing. The structure of the synthesized monomer and crosslinker was confirmed via FTIR (Fourrier Transform Infrared) and 1H NMR (Hydrogen Nuclear Magnetic Resonance) while the physicochemical properties of the 3D printed polymer were investigated using TGA (Thermogravimetric Analysis), DSC (Differential Scanning Calorimeter) and UTM (Universal testing machine). By optimizing the printing conditions and monomer to crosslinker ratio, we can print high-resolution 3D-printed objects. Additionally, in vitro biodegradation, cytocompatibility, and hemocompatibility tests revealed that the printed polymers are biodegradable, cytocompatible, and hemocompatible in nature. More importantly, the printed polymers exhibited strong antibacterial activity against both gram-negative and gram-positive bacteria, suggesting their potential utility in personalized antibacterial medical devices.

Visible Light Induced Degradation of Poly(methyl methacrylate-co-methyl α-chloro acrylate) Copolymer at Ambient Temperature.

Poly(methyl methacrylate) (PMMA) is a well-known and widely used commodity plastic. High production amount of PMMA causes excessive waste creation that highlights the necessity of recycling. Conventional recycling methods require elevated temperatures to induce degradation or depolymerization. In this work, visible light induced photodegradation system by using dimanganese decacarbonyl (Mn2 (CO)10 ) with high halogen affinity is reported. Halide functional photodegradable polymers are prepared by copolymerization of methyl methacrylate and methyl α-chloroacrylate by conventional reversible addition-fragmentation chain-transfer polymerization. Synthesized copolymers are efficiently degraded to low molecular weight oligomers under visible light irradiation in the presence of Mn2 (CO)10 . Characteristics of precursors, degraded polymers, and kinetics of depolymerization are investigated by gel permeation chromatography (GPC), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), Fourrier transform infrared (FTIR), and proton nuclear magnetic resonance (1 H-NMR) spectroscopies. The reported approach is expected to trigger further development of more environmentally friendly recycling techniques in the near future as we are moving toward a greener and more sustainable world.

Biodiesel Production Using Residual Vegetable Oil and Activated by Geopolymer Matrixes with Magnetic Particles

The cooking oil, when reused in frying, undergoes a thermal degradation process that changes its physical and chemical characteristics. After repeated use of the oil, it becomes viscous and increasingly dark, it has high acidity and unpleasant odor, being inconvenient to use for new fried food because it gives unpleasant odor and taste to food and also harmful chemical characteristics to health. When these residues become unusable usually they are dumped into the sewage system and have a negative environmental impact, for example, in rainwater and sanitary sewage systems the oil mixes with the organic matter and obstructs grease boxes and pipes. Therefore, the recycling of residual vegetable oil is necessary and very useful, because it transforms the oil for other applications, for example, in this work the use of porous geopolymer with magnetic particles in the concentrations of 1%, 2%, and 3% were studied for act on the activation of the biodiesel reaction from the used cooking oil. The geopolymers with and without magnetic particles were studied using Fourrier Transform Infrared (FT-IR) and X-Ray Diffraction (XRD). The density, the kinematic viscosity, and yield of the biodiesel formation reaction were investigated. The results, calculated using analysis of variance (ANOVA) with a 95% confidence limit, indicate that all the biodiesel samples analyzed are in accordance with the kinematic viscosity value established by the Agência Nacional do Petróleo, Gás Natural e Biocombustíveis (ANP) but only samples with 0% and 1% magnetic particles have density according to the stipulated parameters.

Structural, morphological and vibrational properties of LaAlO3 nanocrystals produced by four different methods

This work deals with the synthesis of samples of lanthanum aluminate (LaAlO3 - LAO) and their structural, morphological and vibrational properties. The samples were produced by four routes: Sol-Gel with Copaiba Oil; Sol-Gel with coconut oil; Sol-Gel with coconut water and; Modified Pechini. The modified Pechini synthesis was the route used as a reference, as it is well known. In all the rotes, the samples were calcined for 4 h. LAO samples with single-crystalline phase were obtained from 600 °C by Sol-Gel with coconut oil. In the samples obtained via Pechini this phase occurred from 700 °C, and from 800 °C by the other routes. The structural characterization was carried out using X-ray diffraction (XRD) and Fourrier-transform infrared (FTIR) and Raman spectroscopy techniques. The collected XRD patterns were refined by Rietveld method. Morphological characterization was performed with scanning electron microscopy (SEM) and to elemental characterization energy-dispersive X-ray spectroscopy (EDX) was used. Even though the syntheses with natural reagents may leave traces of contaminant elements in samples, they proved to be efficient in producing LAO nanocrystals in the R-3c phase at lower temperatures than those employed in conventional routes.

Poly-(lactic acid) and fibrin bioactive cellularized scaffold for use in bone regenerative medicine: Proof of concept

Bone regenerative medicine (BRM) aims to overcome the limitations of conventional treatments for critical bone defects by developing therapeutic strategies, based on temporary bioactive substitutes, capable of stimulating, sustaining, and guiding tissue regeneration. The aim of this study was to validate the “proof of concept” of a cellularized bioactive scaffold and establish its potential for use in BRM. For this purpose, three-dimensional scaffolds of poly-(lactic acid) (PLA), produced by the additive manufacturing technique, were incorporated into a human platelet-rich plasma (PRP-h) fibrin matrix containing human infrapatellar fat pad mesenchymal stem cells (hIFPMSC). The scaffolds (PLA/finbrin-bioactive) were kept under ideal culture conditions in a medium free from fetal bovine serum and analyzed at 5 and 10 days by Scanning Electron Microscopy (SEM), Fourrier Transform Infrared (FTIR), Circular Dichroism and fluorescence microscopy. The results demonstrated the feasibility of obtaining a rigid, cytocompatible, and cellularized three-dimensional structure. In addition, PRP platelets and leukocytes were able to provide a bioactive environment capable of maintaining the viability of hIFPMSC into scaffolds. The results validate the concept of a customizable, bioactive, cellularized, and non-immunogenic strategy for application in BRM.

Synthesis of alumina by microwave-assisted combustion method using low fuel content and its use as catalytic support for dry reforming of methane

Alumina powders with high specific surface area (>200 m2g-1) were obtained quickly, easily and using only aluminum nitrate and urea (as fuel) through the microwave-assisted combustion method applying low power (450 W) and low fuel content. The powders obtained were calcined at temperatures of 550, 750 and 950 °C. The X-ray diffraction and Fourrier Transform Infrared (FTIR) results indicate that γ-Al2O3 was formed at temperatures of 550 and 750 °C, while the α and γ phases were identified in calcined alumina at 950 °C. The increase in calcination temperature strongly influenced the specific surface area and the pore size distribution, however no effect on the pore diameter was observed. The Al2O3 powder calcined at 550 °C was evaluated as catalytic support due to its most appropriate textural properties. The catalyst Ni/Al2O3 (Ni-A550) was prepared by wet impregnation method and calcined at 550 °C/3 h. The physical-chemistry properties were evaluated by X-ray diffraction, temperature programmed reduction and scan electron microscopy techniques. The results show that the Ni-A550 have high conversion of CH4 and CO2 and good H2 yield using a gas hourly space velocity (GHSV) of 72 L g−1 h−1. Therefore, the synthesized Al2O3 presents as a potential catalytic support material.

Applications of M2ZrO2 (M = Li, Na, K) composite as a catalyst for biodiesel production

Biodiesel is nontoxic and produces little pollution during combustion. It can be used alone or mixed with petroleum diesel as an additive and is a potential alternative fuel. We investigated the use of zirconium dioxide and three alkali metals (Li, Na, and K) for M2ZrO2 (M = Li, Na, K) composites as solid base catalysts for biodiesel production. M2ZrO2 catalysts were prepared using a simple solid-state reaction and by mixing and grinding zirconium dioxide with alkali metals that were calcined at 800 °C in the air for 4 h. The properties of the catalyst were characterized by Field Emission Scanning Electron Microscope (FE-SEM), Brunauer-Emmett-Teller (BET), X-Ray powder diffractometer (XRD), Fourrier Transform Infrared Spectroscopy (FT-IR) and Hammett indicator method, and analyzed the composition of biodiesel by Gas chromatography. The optimum conditions for the process were a Li2ZrO2 calcination temperature of 800 °C for 4 h, a catalyst amount of 6 wt%, a methanol to oil molar ratio of 8:1, and a reaction temperature of 65 °C. The process could transesterify oil into methyl esters at a 98%–99% conversion rate in 2 h for all series. A series of transesterification experiments was conducted to identify the proper operating conditions. The final product met the selected biodiesel fuel properties in accordance with ASTM D6751.

Product investigation of the gas phase ozonolysis of 1-penten-3-ol, cis-2-penten-1-ol and trans-3-hexen-1-ol

Abstract It is well known that the ozonolysis of organic compounds leads to the formation of oxygenated products, which can increase the oxidizing ability of the atmosphere. In this work, the products of the gas phase reactions of ozone with three unsaturated alcohols: 1-penten-3-ol (1P3OL), cis-2-penten-1-ol (c-2P1OL) and trans-3-hexen-1-ol (t-3H1OL) were investigated. The products formation yields were determined at 298 K and 760 Torr, in dry condition, in a 63 L pyrex reactor. The analysis of the products was performed in situ using Fourrier transform infrared (FTIR) spectroscopy (ie technique) and solid phase microextraction sampling in conjunction with gas chromatography coupled to mass spectrometry (SPME/GC-MS) (ie technique). The average yields of primary products were (in %): formaldehyde (62 ± 12) and 2-hydroxybutanal (46 ± 10) for the reaction of O3 with 1-penten-3-ol; glycolaldehyde (56 ± 14) and propanal (40 ± 10) for the reaction of O3 with cis-2-penten-1-ol; propanal (63 ± 8) and 3-hydroxypropanal (43 ± 10) for the reaction of O3 with trans-3-hexen-1-ol. As for secondary products, their average yields were (in %): propanal (12 ± 4) and acetaldehyde (10 ± 4) for the ozonolysis of 1-penten-3-ol; acetaldehyde (13 ± 5), 2-hydroxypropanal (10 ± 2) and methylglyoxal (3 ± 1) for the ozonolysis of cis-2-penten-1-ol, acetaldehyde (30 ± 4), glycolaldehyde (16 ± 4) and methylglyoxal (8 ± 3) for the ozonolysis of trans-3-hexen-1-ol. The obtained yields were compared to the values available in literature. Based on the results obtained in this study, plausible reaction mechanisms of the ozonolysis of these unsaturated alcohols have been proposed.

Synthesis, characterization and evaluation of bioactivity of glasses in the CaO-SiO2-P2O5-MgO system with different CaO/MgO ratios

Bioactive glasses (80Mg, 70Mg, 60Mg and 50Mg) in the system SiO2-CaO-P2O5-MgO were prepared by sol-gel method and then characterized. The structure of the synthesized samples has been studied by X-ray diffraction (XRD), Fourrier Transform Infrared Spectroscopy (FTIR) and Environmental Scanning Electron Microscopy (ESEM). In vitro bioactivity tests were performed in Simulated Body Fluid (SBF). The apparent density and wettability variation with time were measured. The in vitro studies showed the formation of an apatite-like layer covering areas of the material surface. The variation in the CaO/MgO ratio has an influence on the chemical durability and bioactivity. The XRD and FTIR analysis revealed that the samples with larger CaO/MgO ratio exhibited better bioactivity. The results showed that the 50Mg glass which has the higher content of CaO/MgO is hydrophilic sample for the two used fluids (water and SBF). The porosity and hydrophilicity increase with increased the rate of CaO/MgO. The surface of bioglasses became rougher with the increased CaO/MgO ratio, which may lead to a decrease in water contact angle.

Poly[(N-acryloyl glycinamide)-co-(N-acryloyl l-alaninamide)] and Their Ability to Form Thermo-Responsive Hydrogels for Sustained Drug Delivery.

In the presence of water, poly(N-acryloyl glycinamide) homopolymers form highly swollen hydrogels that undergo fast and reversible gel↔sol transitions on heating. According to the literature, the transition temperature depends on concentration and average molecular weight, and in the case of copolymers, composition and hydrophilic/hydrophobic character. In this article, we wish to introduce new copolymers made by free radical polymerization of mixtures of N-acryloyl glycinamide and of its analog optically active N-acryloyl l-alaninamide in various proportions. The N-acryloyl l-alaninamide monomer was selected in attempts to introduce hydrophobicity and chirality in addition to thermo-responsiveness of the Upper Critical Solubilization Temperature-type. The characterization of the resulting copolymers included solubility in solvents, dynamic viscosity in solution, Fourrier Transform Infrared, Nuclear Magnetic Resonance, and Circular Dichroism spectra. Gel→sol transition temperatures were determined in phosphate buffer (pH = 7.4, isotonic to 320 mOsm/dm3). The release characteristics of hydrophilic Methylene Blue and hydrophobic Risperidone entrapped in poly(N-acryloyl glycinamide) and in two copolymers containing 50 and 75% of alanine-based units, respectively, were compared. It was found that increasing the content in N-acryloyl-alaninamide-based units increased the gel→sol transition temperature, decreased the gel consistency, and increased the release rate of Risperidone, but not that of Methylene Blue, with respect to homo poly(N-acryloyl glycinamide). The increase observed in the case of Risperidone appeared to be related to the hydrophobicity generated by alanine residues.

FTIR study of the binary effect of titanium dioxide nanoparticles (nTiO2) and copper (Cu2+) on the biochemical constituents of liver tissues of catfish (Clarias gariepinus).

The increasing demand for nanomaterials and essential metals leads to their discharge into the aquatic ecosystems through water run-off and this is of great concern for the aquatic biodiversity. In the present study titanium dioxide nanoparticles (nTiO2) and copper (Cu2+) effects in binary mixture on the biochemical constituents of the liver of Clarias gariepinus by using Fourrier- transform infrared (FT-IR) techniques was examined. The FT-IR revealed significant differences in absorbance intensities between the control and exposed liver tissues demonstrating changes on the critical biochemical constituents such as proteins, lipids and carbohydrates. This result further reveals the binary mixture responsible for the absence of CH3 bending lipids in liver tissues due to their toxic effect. The observed synergistic decreasing ratio of integrated area (1545/3296) for binary mixture exposed liver tissues suggests that lipid degradation predominates over amide formation. In addition, binary mixture causes an alteration in protein secondary structures by decreasing the β turns of liver tissues. Histology in liver showed marked damages. The frequent alteration in the biochemical constituents in the liver tissues of C. gariepinus could be an indication of alteration of existing biochemical components or the expression of new components.

Removal of arsenic using functionalized cellulose nanofibrils from aqueous solutions.

Cellulose nanofibrils (CNF) functionalized by introduction of trimethylammonium chloride were investigated for the uptake of arsenate [As(V)] from aqueous solutions. The modified-CNF was characterized using Energy Dispersive Spectrometry (EDS), argentometric titration, Boehr titration, zeta-potential, Scanning Electron Microscopy (SEM), Fourrier Transform Infrared (FTIR) spectroscopy, Nuclear Magnetic Resonance (NMR) spectroscopy, Brunauer-Emmet-Teller (BET), and Dynamic Light Scattering (DLS). The modified-CNF was effective for As(V) removal from laboratory and field samples. The As(V) adsorption was rapid and equilibrium was attained within two hours. The kinetic data were adequately described by the pseudo-second-order kinetics model suggesting that As(V) adsorption onto modified-CNF involves electrostatic forces and bonds between As(V) and adsorption sites. The adsorption isotherm data were well correlated with model. The modified-CNF exhibited an As(V) adsorption capacity (qe) of approximately 25.5 mg g-1. Competitive adsorption between As(V) and anions including NO2-, NO3-, and SO42- was investigated and the results showed negligible influence on As(V) removal. However, PO43- presence slightly reduced As(V) adsorption. Thermodynamics study showed that the As(V) adsorption onto modified-CNF is temperature dependent and is spontaneous and exothermic. Overall, the results of this study demonstrated that modified-CNF offers a propitious alterative for As(V) removal from water.

Modification of Montmorillonite with Cetyl Trimethylammonium Bromide and Tetra Ethyl Ortho Silicate

Modification of montmorillonite (MMt) with cetyltrimethylammonium bromide (CTAB) and tetraethyl ortosilicate (TEOS) has been done. The aim of the research is to study the effect of TEOS and CTAB into MMt. This research is a preliminary step to invent material that can be modified with other functional materials. The study was conducted by recting TEOS with MMt and varying CTAB concentration on MMt previously modified with TEOS. The TEOS concentration was 4.72 M while CTAB concentration was 0.25; 0.5; 2; 3.5; and 5 mmol/g in MMt which has been reacted with TEOS. Material characterization was done by X-Ray Diffraction (XRD), Fourrier Transform Infra-Red Spectrophotometer (FTIR) and Scanning Electron Microscope (SEM). Cation exchange capacity (CEC) of materials was analyzed by titration method. The results show that TEOS and CTAB successfully modified. TEOS adsorbed onto MMt. It was identified from increased basal spacing, specific group and also by its elemental composition, originally having basal spacing 16 Å. After modification with CTAB, basal spacing increased to 28.45 Å or 77.64%. This indicates that CTAB is intercalated within the MMt layers. The CEC of new material is 0.93 meq/g, increase from 0.83 meq/g.

Rare Earth Elements Removal from Water Using Natural Polymers

Adsorption of rare earth metals, Eu (III) and Nd (III) was investigated on a new environmental friendly material, thiourea functionalized cellulose. Before usage, the synthesized material was characterized by Fourrier Transform Infrared spectroscopy and energy dispersive X-ray analysis. The influence of adsorption parameters (adsorbent dosage, time, temperature and initial metal concentration) on adsorption capacity was investigated. Experimental data were fitted by using the pseudo-first-order and pseudo-second-order kinetic models. Simultaneously thermodynamic and equilibrium studies have been carried out using Langmuir, Freundlich and Sips isotherm. Maximum adsorption capacities were reached in 30 minutes at 298 K having the value of 27 mg/g for Eu (III) and 73 mg/g for Nd (III).

Enhanced Photovoltaic Performance by Surface Modification of TiO2 Nanorods with Aminopropyltrimethoxysilane (APTMS)

Modification of TiO2 nanorods through the addition of aminopropyltrimethoxysilane (APTMS) for enhancement of efficiency of solar cells has been studied. Synthesis of TiO2 nanorods was conducted through two major stages of mechanochemical and hydrothermal refluxing at a temperature of 120 °C for 24 hours on various concentration of NaOH. Material characterizations were performed by X-Ray Diffraction (XRD), Fourrier Transform Infrared (FTIR) and Transmission Electron Microscope (TEM). Mechanochemical treatment by ball milling showed that the TiO2 phase changed from anatase into brookite and it decreased of TiO2 crystals size. Morphology transformation of TiO2 to form TiO2 nanorods was showed by rod-shaped from TEM micrographs which are characteristic of the nanorods. FTIR spectra confirmed that amine group of aminopropyltrimethoxysilane (APTMS) were successfully grafted onto the TiO2 nanorods surface. Sensitization of TiO2 used Ruthenium complexes N3 (N3=cis-bis(isothiocyanato) bis(2,2′-bipyridyl-4,4′-dicarboxylato ruthenium (II)) were able to increase the uptake of TiO2 material to the visible region due to the absorption of visible light by N3 complex-APTMS. Sensitized TiO2 nanorods were prepared for Dye Sensitized Solar Cell (DSSCs) photoanode. The maximum results of the DSSCs (Dye Sensitized Solar Cell) performance was showed that TiO2 material modified by 10 % (v/v) APTMS capable increase efficiency of DSSCs.

Synthesis and Characterization of Al doped ZnO (AZO) by Sol-gel Method

Al doped ZnO (AZO) nanoparticles have been successfully synthesized by the simple sol-gel method. The starting materials of Al doped ZnO were Zn(CH3COO)2·2H2O and Al(OH)(CH3COO)2. Preparation of AZO using polyethylene glycol as a surfactant. The solution of precursors was stirred at 60 °C for 2 hour in the conditions of Al contents are 0%, 2%, 3% and 4% (g/mL), respectivelly. In the last step reaction, gelation occurred from solution to sol gel. The sol gel then were dried at 60 °C following by annealing process for crystalization. By this simple sol gel method, the nanoparticles have been produced. The characterizations were conducted X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Fourrier Transform Infra-Red (FTIR) and X-Ray Fluorescence (XRF). XRD analysis reveals that all samples has crystallizes in polycrystalline nature and exhibit no other impurity phase. The variation of Al doped ZnO slighly affect the crystallinity and crystal size. Both crystallinity and crystal size decrease with increasing of Al content in AZO. Morphology of AZO shown the particle distribution more equitable with increased Al content. The synthesized AZO gaved shift peak absorption of asymetric and symetric vibrations of Zn-O-Zn around wavelengths of 680 cm-1 and 1630 cm-1 atributed of the uptake of the Al-O-Al bond instead Zn-O-Zn. XRF analysis shown that the increase ratio of Al entering into Zn influenced the Al dopant concentration.

Characteristics of Iron Sand Magnetic Material from Bugel Beach, Kulon Progo, Yogyakarta

Magnetic material (MM) of iron sands from Bugel Beach, Kulon Progo, Yogyakarta has been prepared and characterized. Magnetic material was separated from iron sands using a permanent magnet followed by treating with sodium hydroxide (NaOH) solution. The magnetic material product was characterized with X-ray Fluorescence, X-ray Diffraction, Fourrier Transform Infrared spectrophotometry, and Vibrating Sample Magnetometer to determine the chemical composition, crystallinity, presence of functional groups and the magnetization, respectively. Results showed that the investigated iron sand contained magnetic materials up to 89.47% (w/w). The main composition of MM included Fe2O3, TiO2, and SiO2, with percentages of 72.6, 7.0, and 10.0%, respectively, and the functional groups of material was dominated with Fe–OH and Fe–O. Treatment with NaOH 4M and NaOH 8M increased the content of Fe2O3 and TiO2, otherwise reduced the concentration of SiO2 and contributed to the improvement of the magnetization from 42.1 to 44.3 emu/g (with 4 M NaOH) and 64.0 emu/g (with 8 M NaOH). Additionally, MM was dominated with mineral of magnetite and contained functional groups of Fe–OH and Fe–O.

Synthesis and electrochemical characterization of nanostructured magnetic molecularly imprinted polymers for 17-β-Estradiol determination

The authors report the synthesis, characterization and electrochemical study of a nanostructured magnetic molecularly imprinted polymer (Fe3O4-MIP) for the determination of 17-β-Estradiol (17-β-E2). The synthesized magnetic nanoparticles (Fe3O4-NPs) and Fe3O4-MIP were investigated using High Resolution Transmission Electron Microscopy (HRTEM), High Resolution Scanning Electron Microscopy (HRSEM), X-Ray Diffraction (XRD) and Fourrier Transform Infrared spectroscopy (FT-IR) as characterization techniques. The electrochemical characterization was studied by cyclic voltammetry and electrochemical impedance spectroscopy Several important parameters controlling the performance of the Fe3O4-MIP based sensor such as the choice of electrochemical analysis technique, the frequency, the effect of pH and the incubation time were investigated. Under the optimal conditions, the oxidation peak current was linearly related to 17-β-E2 concentration in the range of 0.05–10μM. The Fe3O4-MIP based sensor amplifies the oxidation current in square-wave voltammetric measurements which allows reaching 20nM as detection limit. Furthermore, the Fe3O4-MIP sensing system exhibits a high selectivity towards 17-β-E2 and was applied successfully for its determination in river water samples.

Composition Variation on Bone Graft Synthesis Based on Hydroxyapatite and Alginate

Bone grafting is a surgical procedure that replaces missing bone with material from patient′s own body, an artificial, synthetic, or natural substitute. As natural bone grows, it generally replaces the graft material completely, resulting in a fully integrated region of new bone. The type of bone graft are allograft-based bone graft involves allograft bone, Factor-based bone graft are natural and recombinant growth , cell-based bone grafts, ceramic-based bone graft substitutes, polymer-based bone graft. The aim of study are to explore the influence of variations in the composition of alginate 8wt % , 10wt % , 12wt % to the characterization and the role of compacting pressure variation to the characterization of hydroxyapatite – alginate and to explore the best composition variation of alginate in which provides the best characteristics for application as a bone graft. All of the materials were mixed with a magnetic stirrer into liquid until homogeny, dried with oven with temperature of 50 °C, and then frozen for optimalizing the drying with sublimation method. The variation of Alginate composition were 8%wt, 10%wt, 12%wt, while the variation of compaction were 1 N/m2, 2 N/m2, 3 N/m2. The sample characterization used Fourrier Transform Infra Red (FTIR) test, compressive strength test, and MTT Assay test. Based on morphology assay, the pore sizes from samples with greater compaction force produces an increasingly smaller pore size. The result showed that variation of hydroxyapatite – alginate composition had effect to compressive strength value. The higher percentage composition of alginate, the greater pressure will increase the value of its compressive compaction and strength. The result of cytotoxicity test showed that nine samples were non toxic. In this research, the sample with composition 12% wt alginate and 3 N/ m2 in compaction was the best characteristic according to mechanical aspect.

Fourrier Transform Infrared and Gel Permeation Chromatography Evaluation to Prepared Polyurethane Paint from Polyol Palm Oil Based

A New emulsion type paint was prepared by utilizing polyol for the production of polyurethane by reaction with an isocyanate was obtained by the synthesis of palm oil-based oleic acid with glycerol. Dodecylbenzene sulfonic acid (DBSA) was used as catalyst and emulsifier. The various methods for preparing Polyurethane /clay nanocomposites, but in this research the author choice by a pre-polymer method and were evaluated by fourier transform infrared (FTIR) spectra to determine micro-domain structures of segmented PU. The molecular weight (MW) of polyol was obtained by using gel permeation chromatography (GPC) and the result was about 950. The micro domain structures of the segmented PU were analyzed by FTIR by following the work of Seymour, et.al. to estimated the degree of phase separation in segmented PU. The formation of hydrogen bonding by C=O group can be determined by examining the peak position at 1709 cm-1 for hydrogen bonded C=O and at 1731 cm-1 for free C=O. The molecular weight (MW) of PU based on palm oil was about 3.266. The performance characteristics of materials indicate to be comparable with the corresponding industrial standard.