Green Preparation of Lightweight, High-Strength Cellulose-Based Foam and Evaluation of Its Adsorption Properties

Hydrophobic bio-based foam prepared from recycled pulp fiber and its properties

Compared with traditional petroleum-based foam materials, cellulosic foam materials have significant advantages in terms of economy and environmental protection. However, the traditional cellulose-based foams have some problems such as high energy consumption in the preparation process. In this study, the recycled pulp foam (RPF) with ultra-light density (12.69 kg/m3 ~ 13.83 kg/m3) and high porosity (99.07 % ~ 99.15 %) was prepared by mechanical stirring using waste corrugated cardboard as the main raw material and further hydrophobically modified using rosin. The prepared r-RPF foam has excellent hydrophobicity with the water contact angle remaining 132.9° after 20 s. In addition, the rosin coating enhances the mechanical properties of r-RPF, and the stress of r-RPF at 50 % strain is increased by 97 %. It should be noted that after rosin treatment, the compressive strength and elasticity of r-RPF were improved. The r-RPF was stable in water and had a high oil adsorption capacity (7.8 to 28.13 g/g), which had the potential to treat current oily wastewater.

Applications of Xylan Derivatives to Improve the Functional Properties of Cellulose Foams for Noise Insulation

Cellulose-based foams present a high potential for noise insulation applications. These materials are bio-degradable, eco-friendly by both embedded components and manufacturing process, have low density and high porosity, and are able to provide good noise insulation characteristics compared with available petroleum-based foams currently used on a large scale. This paper presents the results of some investigations performed by the authors in order to improve the functional characteristics in terms of free surface wettability and structural integrity. Native xylan and xylan-based derivatives (in terms of acetylated and hydrophobized xylan) were taken into account for surface treatment of cellulose foams, suggesting that hemicelluloses represent by-products of pulp and paper industry, and xylan polysaccharides are the most abundant hemicelluloses type. The investigations were mainly conducted in order to evaluate the level to which surface treatments have affected the noise insulation properties of basic cellulose foams. The results indicate that surface treatments with xylan derivatives have slowly affected the soundproofing characteristics of foams, but these clearly have to be taken into account because of their high decrease in wettability level and improving structural integrity.

Cellulose Fibers-Based Porous Lightweight Foams for Noise Insulation

This paper examines effective and environmentally friendly materials intended for noise insulation and soundproofing applications, starting with materials that have gained significant attention within last years. Foam-formed materials based on cellulose fibers have emerged as a promising solution. The aim of this study was to obtain a set of foam-formed, porous, lightweight materials based on cellulose fibers from a resinous slurry pulp source, and to investigate the impact of surfactant percentage of the foam mixtures on their noise insulation characterisitcs. The basic foam-forming technique was used for sample assembly, with three percentages of sodium dodecyl sulphate (as anionic surfactant) related to fiber weight, and a standardised sound transmission loss tube procedure was used to evaluate noise insulation performance. Results were obtained as observations of internal structural configurations and material characteristics, and as measurements of sound absorption/reflection, sound transmission loss, and surface acoustic impedance. Based on the findings within this study, the conclusions highlight the strong potential of these cellulosic foams to replace widely used synthetic materials, at least into the area of practical noise insulation applications.