# Properties of Emulsion Paint with Modified Natural Rubber Late/Polyvinyl Acetate Blend Binder
## 3 Results and Discussion
### Properties of Set Touch Drying Time of Emulsion Paints  
The set touch drying time is the time it takes for the emulsion paint to reach a certain dryness level when touched. The touch dry time is known if the media being touched leaves no touchmarks on the surface of the painted media. The set touch drying time test results showed that the emulsion paint sample was experienced a maximum drying of under 2.5 h with three coats of paint, as shown in Table 3. The nature of the set touch drying time of the emulsion paint increased with each increase in NRL and LNR in the binder mixture. This is because the modified NRL and LNR still absorb some of the water contained in the paint, thus slowing down the drying process of the paint. In addition, polymers with many cross-links will also prolong the drying process [16].  
\begin{table}
\begin{tabular}{c c c c c c} \hline \hline \multirow{2}{*}{**Sample**} & \multicolumn{5}{c}{**Opacity (\% Absorbance) with PVA Ratio**} \\ \cline{2-6}  & **0:100** & **1580** & **2575** & **35:65** & **50:50** & **100:0** \\ \hline NRL/PVAc Binder 4\% & 1.6346 & 1.6359 & 1.6192 & 1.5387 & 1.5644 & 1.593 \\ NRL/PVAc Binder 6\% & 1.6193 & 1.6309 & 1.6216 & 1.5611 & 1.5476 & 1.5923 \\ NRL/PVAc Binder 8\% & 1.6169 & 1.6426 & 1.5957 & 1.649 & 1.5802 & 1.5355 \\ LNR/PVAc Binder 2\% & 1.6093 & 1.6989 & 1.5734 & 1.6342 & 1.4943 & 1.6355 \\ LNR/PVAc Binder 4\% & 1.6346 & 1.6292 & 1.6151 & 1.6098 & 1.5823 & 1.6313 \\ LNR/PVAc Binder 6\% & 1.6193 & 1.6013 & 1.721 & 1.653 & 1.6099 & 1.5788 \\ LNR/PVAc Binder 8\% & 1.6169 & 1.6144 & 1.6142 & 1.6417 & 1.6055 & 1.7298 \\ NRL-g(MMA-co-St) 60:40 & 1.6346 & 1.6961 & 1.693 & 1.6698 & 1.6589 & 1.5267 \\ NRL-g(MMA-co-St) 60:53 & 1.6346 & 1.5205 & 1.3726 & 1.4448 & 1.3532 & 1.4177 \\ NRL-g(MMA-co-St)70:30 & 1.6346 & 1.637 & 1.5653 & 1.4196 & 1.5645 & 1.4096 \\ NRL-g(MMA-co-St)70:525 & 1.6346 & 1.3897 & 1.42 & 1.2402 & 1.1751 & 1.3511 \\ NRL-g(MMA-co-St)80:200 & 1.6346 & 1.7782 & 1.7673 & 1.7655 & 1.7533 & 1.7159 \\ LNR-g(MMA-co-St)60:40 & 1.6346 & 1.6708 & 1.6383 & 1.6451 & 1.6338 & 1.5689 \\ LNR-g(MMA-co-St)60:535 & 1.6346 & 1.5036 & 1.6143 & 1.6699 & 1.5743 & 1.5485 \\ LNR-g(MMA-co-St)70:525 & 1.6346 & 1.5624 & 1.4107 & 1.5309 & 1.3856 & 1.5281 \\ LNR-g(MMA-co-St)70:30 & 1.6346 & 1.4728 & 1.5118 & 1.3575 & 1.2358 & 1.6171 \\ LNR-g(MMA-co-St)80:20 & 1.6346 & 1.5844 & 1.4826 & 1.3422 & 1.1793 & 0.9267 \\ \hline \hline \end{tabular}
\end{table}
Table 2: Opacity properties of emulsion pains on various binder variations.  
The set touch drying time was fastest in the emulsion paint sample with mixed content of 15/85 LNR/PVAc binder with a concentration of 4% in the emulsion paint. This is due to the lower carbon chain length and molecular weight of LNR than NR, so the water particles trapped on the LNR surface will evaporate more quickly. In addition, the diffusion of oxygen particles is also easier in the emulsion paint samples with the LNR/PVAc mixed binder and this results in a faster oxidative polymerization process. The mixed LNR/PVAc binder with a ratio of 15:85 produces emulsion paint with a quicker set touch drying time, even when using only PVAc binder.