PAPERmaking! FROM THE PUBLISHERS OF PAPER TECHNOLOGY Volume 5, Number 2, 2019
wet strength of 50 MPa. Adding lignin also improves the thermostability and UV Ǧ blocking performance of cellulose paper. The demonstrated lignin Ǧ cellulose composite is biodegradable and eco Ǧ friendly with both components from natural wood, which represents a promising alternative that can potentially replace the nonbiodegradable plastics. Poly(lactic acid) composites reinforced with kraft pulp fibres: Production by a papermaking process and characterisation, Sónia Sousa et al, Composites Part A: Applied Science and Manufacturing , 121, pp.273-282. Four different pulp fibres, representing short and long cellulose fibres and chemically modified fibres, were tested as reinforcements for poly(lactic acid) composites. A simple papermaking method was used to form the composite sheets, which were further compression moulded. The effects of morphological, chemical, and mechanical characteristics of kraft pulp fibres and their contents on the PLA composite characteristics were investigated. The incorporation of kraft pulp fibres provided composites with 16 – 24% and 36 – 39% higher tensile strength and Young’s modulus values, respectively, than those of neat PLA. Unbleached pulp fibres, which had higher intrinsic strength than that of the corresponding bleached pulp, provided composites with higher tensile properties. In the tested range, the effect of the cellulose fibre length was not significant. Compared to those of neat PLA, barrier properties for water vapour and oxygen were slightly superior for composites incorporating up to 30% (wt) of kraft pulp. PACKAGING TECHNOLOGY Measurement of thermal conductivity of paper and corrugated fibreboard with prediction of thermal performance for design applications, E. M. Gray-Stuart et al, Cellulose , 26 (9), pp.5695 – 5705 . Understanding heat transfer in corrugated fibreboard is important to the design of more effective packaging for industries which involve the freezing and chilling of food. In this work the thermal conductivity of papers which compose corrugated fibreboard were measured and used to validate finite element models of heat transfer in fibreboard. The results showed paper to be highly anisotropic, with thermal conductivity in the machine and cross machine directions being almost an order of magnitude larger than in the thickness direction. The finite element models showed good agreement with experimental results and demonstrated that the majority of heat transfer in corrugated fibreboard is though the fluted medium. Based on the finite element models, simple models for the prediction of the thermal performance of corrugated board were evaluated and shown to be very effective in reproducing the results of the more complex finite element methods. These simple methods can be used to perform corrugated fibreboard design calculations, and the models with and without radiation can be used to provide estimates of the lower and upper bounds of the thermal resistance for a given board design. An overview of paper and paper based food packaging materials: health safety and environmental concerns, Gaurav Kr Deshwal et al, Journal of Food Science and Technology , 56 (10), pp.4391 – 4403. Pulp and paper industry is one of the major sector in every country of the globe contributing not only to Gross Domestic Product but surprisingly to environmental pollution and health hazards also. Paper and paperboard based material is the one of the earliest and largest used packaging form for food products like milk and milk based products, beverages, dry powders, confectionary, bakery products etc. owing to its eco-friendly hallmark. Various toxic chemicals like printing inks, phthalates, surfactants, bleaching agents, hydrocarbons etc. are incorporated in the paper during its development process which leaches into the food chain during paper production, food consumption and recycling through water discharges. Recycling is considered the best
Technical Abstracts
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