Abstract:
Cellulose nitrate (CN) is a semi-synthetic polymer rendering outstanding film properties such as good transparency, and water resistance, thus finds its major utilization in coating industry. Raw CN has water and isopropyl alcohol by-product at maximum content of approximately 3 and 30 wt%, respectively. The tolerance water level in the CN powder for a potential application as nail polish is investigated in order to produce good film-forming properties. The effect of adding layered silicate clay particles as thixotropic agent in the nail enamel is also examined. The water content was varied at different weight percent i.e. 1, 2, 3, 4, 6, 8 and 10 wt%. It was found that the increase in water content affected the solution properties of CN by reducing its viscosity and drying time but it has no more effect to the dried films. According to poor adhesion of CN, adhesion promoter types were investigated for CN adhesion improvement. The suitable adhesion promoters are epoxy and maleic resin which is liquid and solid at room temperature, respectively. The compositions of maleicepoxy mixture were investigated by varying resin ratio 10:0, 8:2, 5:5, 2:8, and 0:10 wt%. At composition 5:5 provides relatively good durable film. Thixotropic suspension preparation was compared mechanical stirrer preparation at 650 r.p.m. for 4, 8, 14, 24, and 48 hr. with homogenizer at 6.5 x 10[superscript 3], 9.5 x 10[superscript 3], 13.5 x 10[superscript 3], 21.5 x 10[superscript 3], and 24 x 10[superscript 3] r.p.m. for 5 minutes. The suspension preparing by homogenizer furnishes higher viscosity and produces gel in short time, dried film also show fined texture which is higher gloss than motor stirrer preparation. Three kinds of organoclay using as suspension in toluene were dimethyl dioctadecyl ammonium hectorite, dimetyl benzyl dodecyl ammonium bentonite, and dimethyl dioctadecyl ammonium bentonite varying contents from 1-5 wt%. The suitable content is about 5 wt% where able to suspend pigment without hard packed settling.
