Anika Zafiah M. Rus

Polymers from Renewable Materials

With the world facing depletion of its oil reserves, attention is being focused on how the plastics industry will address shortages and price increases in its crucial raw materials. One renewable resource is that of vegetable oils and fats and about a dozen crop plants make up the main vegetable oil-seed market. The main constituents of these oils are saturated and unsaturated fatty acids that are unique to the plant in which they have been developed. Moreover, technological processes can produce more well-defined and pure oils, and the fatty acid contents in the vegetable oils can be altered with modern crop development techniques. This article describes recent advances in utilising such vegetable oils in sourcing new polymeric materials. It also gives the context for the development of polymers based on renewable materials in general.

Acoustic Study Based on Sustainable Green Polymer Treated with H2O

Green polymer foam was prepared by the reaction of green monomer based on vegetable oil with commercial Polymethane Polyphenyl Isocyanate (Modified Polymeric-MDI) and distilled water (H2O). The morphological study of green polymer foam was examined by Scanning Electron Microscope (SEM) and acoustic property by means of H2O composition ratio equivalent to weight of polyol. It was found that the cell size of green polymer foam has significantly increment as well as H2O loading increased. Increasing of H2O more than 50% equivalent to weight of polyol shows nonuniform pore distribution, large average pore size and smallest number of pore. Furthermore, the cell size of neat green polymer foam gives 400μm up to 1833.3μm with high loading of H2O. In addition, the cell size of green polymer foam influences by the increasing amount of H2O loading and enhanced the sound absorption property at low frequency level.

Degradation studies of polyurethanes based on vegetable oils. Part 1. Photodegradation

UV-induced photodegradation has been studied of films of polyurethanes synthesised from (renewable) vegetable materials, namely rapeseed and sunflower oils. The techniques utilised were principally IR and UV-visible spectroscopy. UV(B)-photolysis of the cured films gave rise to IR bands in the carbonyl region at ca 1706 cm-1 and a UV band at 310 nm attributed to formation of a quinone methide, an assignment supported by the development of new IR bands at 1595, 1650, and 1695 cm-1 which are typical of this chromophore. In addition, intensification of a band at 1171 cm-1 is attributed to cross-linking of the soft segments in the polymer. Plots of the growth of the 1706 cm-1 band on irradiation over time showed the usual profile for conversion of CH2 groups to carbonyl: these were normalised against the band at 2900 cm-1 of the polymer to give the carbonyl index (CI). The effect of adding the pigment TiO2 on the CI was monitored. The effect depended strongly on the nature of the TiO2; thus the Degussa P-25 pigment greatly accelerated photodegradation whereas TiO2 coated with a thin layer of silica or alumina, as in Kronos 2220 pigment, conferred photostability on the polymer. Doping the TiO2 with metal ions markedly affected its behaviour; addition of Mo(VI) made the TiO2 more aggressive while doping with Cr(III) reduced its activity. Addition of the photostabiliser Tinuvin 770 had a dramatic effect in reducing the photo-oxidation of the polyurethanes.

Biopolymer doped with titanium dioxide superhydrophobic photocatalysis as self-clean coating for lightweight composite

The development of a lightweight composite (LC) based on Portland cement concrete with waste lightweight aggregate (WLA) additive was carried out to improve the sustainability and environmental impact and to offer potential cost savings without sacrificing strength. Treatment of the surface of the LC exposed to environmental attack by coating with biopolymer based on waste cooking oil doped with titanium dioxide photocatalysis (TOP) with superhydrophilic property was found to affect the mechanical properties of the LC in a systematic way. The results of compressive strength showed that the composite achieved the minimum required strength for lightweight construction materials of 17.2 MPa. Scratch resistance measurements showed that the highest percentages loading of superhydrophilic particles (up to 2.5% of biomonomer weight) for LCs surface coating gave the highest scratch resistance while the uncoated sample showed the least resistances. Scanning electron microscope (SEM) pictures revealed the difference between the surface roughness for LC with and without TOP coating. TOP is also formulated to provide self-cleaning LC surfaces based on two principal ways: (1) the development by coating the LC with a photocatalytic superhydrophilic, (2) if such a superhydrophilic is illuminated by light, the grease, dirt, and organic contaminants will be decomposed and can easily be swept away by rain.

Influence of Bio Polymer Composites as Heat Absorption Coating

The purpose of this research is to study the reduction of internal temperature and heat absorption of building prototype after coated with bio polymer composites. Waste cooking oil has been treated with chemical process and mixed with Methylene Diphenyl Diisocyanate (MDI) and Titanium Dioxide (TiO2) to produce polymer coating. K-Type thermometer was employed to measure the outside and inside temperature before coated and after coated with bio polymer. The external surface of prototype building the roof was coated with bio polymer up to 3 layers, with 0.50 mm thickness for each layer. The measured temperature shows the reduction of the outside roof temperature is 13.65 °C, while the reduction of the inside roof temperature is 12.61 °C. This reduction of temperature is influenced by the thickness of the bio polymer coating.

Influences of Thickness and Fabric for Sound Absorption of Biopolymer Composite

Biopolymer foam was prepared by the reaction of bio-monomer based on vegetable oil with commercial Polymethane Polyphenyl Isocyanate (Modified Polymeric-MDI). The acoustic study of biopolymer foam was examined by impedance tube test according to the ASTM E-1050 and laminated with three types of textile such as polyester, cotton and single knitted jersey. It was revealed that the thicker the fabric the higher the sound absorption coefficient (α) at medium frequency level. The higher the number of layers or thickness of the fabric, the sound absorption through the fabric increases at medium frequency but after the maximum it remains almost unaltered. Three layer of cotton fabric gives maximum α approximately equal to 1 which is 1.104 mm thickness at frequency level of 3000-3500Hz and single knitted jersey gives maximum α at 4th layer of 2200-2700Hz. Meanwhile , the α of biopolymer foam laminated with polyester fabric approximately equal to 1 at lower frequency level of 2000-3000Hz with lower thickness that is 0.668mm. Polyester fabric with lowest thickness shows better α at lower frequency level due to the structure of the fabric. The relationships among the fiber properties such as fiber density, fiber diameter, and fibrous material layer were considered as a factor that influences the sound absorption property.

Effect of Thickness for Sound Absorption of High Density Biopolymer Foams

Waste cooking oils are problematic disposal especially in the developed countries. In this paper, waste cooking oil is used as raw material to produce foam. The purpose of the study is to develop the high density solid biopolymer (HDB) by using hot compression moulding technique based on flexible and rigid crosslinking agents. Physical properties such as Scanning Electron Microscope (SEM) and density of HDB were examined. The acoustic study of HDB for flexible and rigid has been measured using impedance tube test according ASTM E1050 standard with multiple layers of thicknesses. It was revealed that higher thicknesses of HDB exhibit less sound absorption coefficients. This situation is occurred for both flexible and rigid HDB. The frequency also shifted to the left when the layers of HDB were increased for both materials. The highest increment was 63.46%, observed from two layers from flexible and rigid HDB. For the conclusion, rigid HDB showed that they could absorb more sound, thus having higher noise reduction coefficient (NRC) than flexible HDB at low frequency.

Preliminary Fabrication of Polymer Membranes from Renewable Resources

Polymer membranes from renewable material with controlled pore size and structure were produce using phase inversion technique. The optimal conditions for the preparation of polymer membranes was polymer concentrations in N,N-dimethylformamide (DMF) solution 12 % (w/v), 15 % (w/v), 18 % (w/v) and 21 % (w/v). This is due to the types of structure; pinhole-like structure and interconnected network structure. The structure of the membranes consisted of thick fibrill elements. The polymer membrane cross-section is composed of stacks of separate layers. Permeability of the polymer membranes obtained at lower concentrations, gives highest value of 0.161, 0.015, 0.001 and 0.00051 L/s.m3 for 12 %, 15 %, 18 % and 21 % (w/v) respectively. Evidently, as the concentration of the polymer in DMF increases, the tear strength decreases. Meanwhile, for lower concentration in N,N-dimethylformamide (DMF), gave highest strength due to low membranes wall thicker. Thus, the membranes are easily break compared to the membranes that have high porosity as shown by tear test of 12 % with 21.8495 N/mm tear strength.

Influence of Multilayer Textile Biopolymer Foam Doped with Titanium Dioxide for Sound Absorption Materials

Biopolymer foam was prepared by the reaction of bio-monomer based on vegetable oil with commercial Polymethane Polyphenyl Isocyanate (Modified Polymeric-MDI) and titanium dioxide (TiO2). The acoustic study of biopolymer foam with 2.5% TiO2 loading was examined by impedance tube test according to the ASTM E-1050 and laminated with three types of textile such as polyester, cotton and single knitted jersey. It was revealed that the thicker the fabric the higher the sound absorption coefficient (α) at low frequency level. The higher the number of layers or thickness of the fabric, the sound absorption through the fabric increases at low frequency but after the maximum it remains almost unaltered. Three layer of cotton fabric gives maximum α approximately equal to 0.578 which is 1.472mm thickness at low frequency level of 1000-2000Hz and single knitted jersey gives maximum α at 3th layer. Meanwhile , the α of biopolymer foam with 2.5% TiO2 loading laminated with polyester fabric approximately equal to 1 at lower frequency level of 1000-2000Hz with lower thickness that is 0.668mm. Polyester fabric with lowest thickness shows better α at lower frequency level due to the structure of the fabric. The relationships among the fiber properties such as fiber density, fiber diameter, fibrous material layer were considered as a factor that influences the sound absorption property.

Influence of Hot Compression Moulding of Particulate Biopolymer and their Sandwich Layups for Sound Absorption Characteristic

Waste cooking oils are problematic disposal especially in the developed countries. In this paper, waste cooking oil is used as raw material to produce foam. The purpose of the study is to develop the high density solid biopolymer (HDB) by using hot compression moulding technique based on flexible and rigid crosslinking agents. Physical properties such as Scanning Electron Microscope (SEM) and density of HDB were examined. The acoustic study of HDB sandwich layups of flexible (F) or rigid (R) has been measured using an impedance tube test according ASTM E1050 standard up to four maximum sandwich lay ups of F and R HDB in different arrangement. It was revealed that the arrangement sandwich layups of FRRF HDB sandwich gives the lowest sound absorption coefficients. The resonance frequency for RFR, FRF and FRRF were shifted to the left except for RFFR. The highest increment was 35.7 %, observed from RFR compared to the three layers of sandwich HDB. For the conclusion, RFR HDB showed that could absorb more sound, thus having higher noise reduction coefficient (NRC) than the other sandwich layups HDB at low frequency.