2.) Simple and Effective UV-assisted Synthesis of Silver Nanoparticles in Polymethacrylic Acid
4.) Total Phenolic Content and Textile Dye Performance of Dried Coffea robusta (Coffee) Mesocarp
5.) Mechano-Physical Properties of Enzyme-Treated Musa textilis (Abaca) Fibers
Julius L. Leaño Jr.
Abstract
Crude aqueous extract of young coconut (Cocos nucifera) husk was used to dye fabrics made of Musa Textilis (Abaca), knitted cotton, Ananas comosus (pineapple), pineapple-silk, fine (21D) silk and coarse (360D) silk. Colorimetric evaluation revealed that generally alum lightens the color, while CuSO4 tends to darken it. The use of CuSO4/alum mordant system revealed the almost equal influence of each mordant in the resulting L value except in the case of fine silk and M. textilis fabrics where the darkening effect of CuSO4 predominated. Incremental changes caused by varying the mordants were observed in the corresponding a and b values. Higher color strength, K/S values were obtained on fabrics using alum mordant compared to pure CuSO4 or their combination. Further, colorfastness to laundering (AATCC 61-2003) ratings are in the range of 3-4, although predominantly, the laundered samples all turned darker and qualifying the observed change not due to fading but to darkening. The corresponding staining ratings were in the range of 3.5-4.5 using multi-fiber No. 1. The colorfastness to perspiration (AATCC 15-2002) ratings were in the range of 3.5-4.5 with observed yellowing. The staining ratings were in the range of 3-4.5, but ratings of 2 were mostly on cotton mordanted with CuSO4. All the other ratings of the dyed fabrics comply with the minimum staining ratings specified by Oeko Tex 100. The use of CuSO4/alum mordant system further diversified the colorway of C. nucifera as it generally maintained the performance of the dyed fabrics compared when using either pure 5% CuSO4 or 5% alum as mordants.
Simple and Effective UV-assisted Synthesis of Silver Nanoparticles in Polymethacrylic Acid
Evangeline Flor P. Manalang and Jeannie Lynn J. Cabansag
Abstract
A simple, inexpensive, and intrinsically non-toxic method of preparing silver nanoparticles via UV- include reduction of silver ions using polymethacrylic acid (PMA) is reported. Parameters such as source of radiation, concentrations of AgNO3 and PMA and duration of irradiation were optimized to establish a technique of synthesizing silver nanoparticles with minimized aggregation. The radiation sources, mechanical action, reactant concentration, and irradiation time have significant effect on the preparation of Ag NPs; and they can be varied to control its size, shape and distribution. Results revealed that 10:1 millimolar ratio of AgNO3 and PMA and 1 h UV irradiation using 8 W UV C lamp with continuous stirring are the optimized condition for the preparation of Ag NPs. Using the optimized parameters, characteristic SPR band at 430 nm wavelength was observed via UV-Vis spectroscopic technique. This confirmed the effective conversion of Ag+ to Ag0 and the formation of spherical Ag NPs with minimized agglomeration. This method has great potential for scaled-up production of Ag NPs for various industrial applications.
Gilbert V. Gomez, Francis M. dela Rosa, Argentina T. Cariño, and Julius L. Leaño Jr.
Abstract
Monochlorotriazinyl-?-cyclodextrin (MCT-?-CD), 4 was synthesized from cyanuric chloride, 1 and ?-cyclodextrin, 3. The synthesized MCT-?-CD was applied to cotton and cotton-polyester (50/50 and 65/35) by pad-dry-cure method. Subsequent characterization of the grafted fabrics through Fourier Transform Infrared-Attenuated Total Reflectance (FTIR-ATR) Analysis revealed the successful grafting of MCT-?-CD, 4 into cotton and cotton-polyester fabrics with the appearabce of characteristic peaks at 1489 cm-1 and 1404 cm-1. Further, the grafted fabrics through Energy Dispersive Spectroscopic (EDS) Analysis revealed the presence of Nitrogen, indicative of the presence of the synthesized MCT-?-CD, 4 on the surface of cotton and cotton-polyester fabrics, Durability test revealed that MCT-?-CD-grafted cotton and cotton-polyester fabrics can withstand at least one washing cycle.
Total Phenolic Content and Textile Dye Performance of Dried Coffea robusta (Coffee) Mesocarp
Julius L. Leaño Jr., Neil Jhon G. Tadeo, and Evangeline Flor P. Manalang
Abstract
The total phenoloc content (TPC) of the Robusta coffee (Coffea robusta) pulp was successfully determined using Follin-Ciocalteu assay. Different factors, such as extraction methods, sample to solvent ratio, solvent system, temperature, rate, and duration, effect the amount of TPC extracted. Based on the result, refluxing with 50:50 EtOH-H2O is the best extraction solvent-system and approach. The crude coffee pulp extracts were freeze dried and was found to have the highest powder yield of 54.6% from extraction by boiling in water. The powdered extract was characterized using FTIR-DRS and UV-Vis Spectroscopy. FTIR spectrum showed the presence of peak corresponding to alcoholic O-H, alkyl C-H and aromatic C=C vibrations. UV-Vis spectrum showed a maximum peak at 312 nm corresponding to the electronic transitions of ? electronics in the benzene ring of the polyphenolic compounds. Results confirmed the presence of polyphenolic compounds as earlier detected by Folin-Ciocalteu assay. Dye potential of the coffee pulp powder was investigated and was found to impart light brown color to pineapple (Ananas comosus), abaca (Musa textilis), silk (Bombyx mori) and pineapple-silk) fabrics. Results further revealed that the dyed fabrics, whether pre-mordanted or not, showed satisfactory performance to colorfastness laundering and perspiration tests and these colorfastness properties proved that C. robusta mesocarp is a promising textile dye source.
Mechano-Physical Properties of Enzyme-Treated Musa textilis (Abaca) Fibers
Jeannie Lynn J. Cabansag and Julius L. Leaño Jr.
Abstract
Treatment of knotted abaca (Musa textilis) fibers with enzymes affording the subrate specific removal of noncellulosic impurities such as pectin, fats, waxes, lignin, and xylans was studied and compared with the conventional alkaline method of scouring.
M. Textilis fibers were treated with commercially available pectinase, cellulase, protease, and xylanase at varying pH, temperature, surfactant and enzyme concentrations, and treatment duration. Physico-mechanical properties of treated fibers were evaluated in terms of % weight loss, whiteness, and tensile strength and compared with alkaline scoured fibers. Whiteness index was assessed using the CIE L*a*b* data expressing color in tri-stimuli values. Results showed that the efficiency of enzyme treatment on the fibers were comparable with the mechanical properties of alkaline treated fibers and exhibited better tensile strength. The use of enzymes in pre-treating M. textilis fibers offers a greener alternative to the conventional alkaline pre-treatment process.
