HUNAN XIEYING PACKAGING CO.,LTD

Paper products are commonly coated with plastics for two major desired properties: (1) water proofing as in the case of disposable paper cups, plates, etc. and (2) greaseresistance as in the case of take out boxes, pizza-boxes, etc. Water proofing is measured using a Cobb test where amount of water absorbed by the paper in a given time indicates the relative water resistance of the paper. Lower the uptake of water better is the performance. As shown in Figure 4 the performance of modified-PLA coated paper (samples from Natur-Tec) was comparable to that of PE-coated paper and significantly improved compared to the uncoated paper. Although the coatings were applied at different weights the thickness was the same order of magnitude based on density of the two resins. Grease resistance of the papers was measured using the 3M kit test – twelve kit solutions are prepared by mixing different amounts of Castor oil, n-Heptane and Toluene and the lowest number of solution that stains the paper in 15 seconds is recorded. As shown in Table 1 both the coated papers passed all the twelve test solutions and had a high degree of grease resistance compared to the base paper. The PLA-based paper performed at par with the PE coated samples in terms of properties for both water and grease resistance