The study is aimed to find whether the location of the calcium carbonate added in a three-layer co-extruded blown film has an impact on film's barrier and mechanical properties. Aragonite calcium carbonate-added low-density polyethylene films were produced at various weight ratios and layer structure through a three-layer co-extrusion blown film line. The scanning electron microscopy micrographs were obtained to understand the dispersion on the calcium carbonate and the morphology related to the film barrier and mechanical properties. The study found that adding calcium carbonate into the center layer of the three-layer co-extruded blown film significantly enhanced the barrier properties. The oxygen and water vapor barrier of the blown film improved 50% and 40%, respectively, in the presence of 18.38 wt% calcium carbonate. Adding calcium carbonate into the center layer does not change the tensile strength of the blown film to a great extent when the filler concentration is between 9.12 wt% to 18.38 wt%. However, the addition of the calcium carbonate reduced the film's impact strength by 50 to 70% in the presence of 9.17 wt% to 31.54 wt% calcium carbonate for both center layer reinforced and blended blown film.

This article investigates three-layer co-extruded blown film comprised of low-density polyethylene (LDPE)/ethylene–vinyl alcohol (EVOH)/LDPE without adhesion layers. Various thicknesses of pure EVOH were sandwiched by outer LDPE layers blended with linear low-density polyethylene-grafted-maleic anhydride (LLDPE- g-MAH) as compatibilizer in concentrations from 0 wt% to 2.0 wt%. The study found that a mere 3-μ EVOH layer can achieve a 180 times improvement of oxygen barrier properties as compared to the control sample. When the EVOH loading is 10–15 wt% of the total film mass, the addition of LLDPE- g-MAH into the outer layers indicated a positive synergistic effect by enhancing barrier properties. In contrast, when the EVOH loadings are at 5 wt% and 7.5 wt%, the barrier properties of the film was reduced. Layer-to-layer interaction between the LDPE and EVOH was notably improved as demonstrated by a 26–42% increase of interlaminate peel strength in the presence of 0.5–2 wt% LLDPE- g-MAH in all samples. Congruently, the introduction of the LLDPE- g-MAH into the outer LDPE layers also resulted in an increased dart impact toughness and tensile strength for the film. The EVOH crystallinity showed a reduction after adding LLDPE- g-MAH, particularly apparent for the lower EVOH concentrations.

Second generation bioethanol is produced from lignocellulose which comes from agricultural waste instead of agricultural feedstock. This study utilized the residuals from the extraction of C5 and C6 sugars in the second generation bioethanol while 20 and 40 wt % of the biomass was blended with starch into a starch/biomass foam. After adding the biomass into starch foam, the morphology of the starch foam changed significantly, showing rough surfaces, higher cell densities, as well as smaller cell areas than the starch only foam. Adding the biomass into the starch overall resulted in the reduction of the compressive strength, the stiffness, and the density of the starch foam. The water sensitivity of the starch foam/biomass was reduced by 60%, indicating a significant improvement of the hydrophilic nature of the starch foam. The foam/biomass demonstrated a lower thermal stability than neat starch foam due to the decomposition of the biomass. The study concluded that the biomass from the second generation cellulosic ethanol process possess similar physical, mechanical, and thermal properties as the other starch foam composite, and yet, no additive is required.