Mechanical properties of polymer–paper laminates

Abstract

SynopsisTensile mechanical properties of synthetic polymer-paper laminates were measured. The laminates were constructed by hot pressing a sandwich made of a sheet of paper between polymer films. There is complete penetration of the polymer inside the paper; no voids are left. Two different polymer matrices were used poly(methy1 methacrylate) and polyethylene. Several paper samples were utilized: an unoriented holocellulose paper (a strong paper), a highly oriented holocellulose paper, and an unoriented Whatman filter paper (a weak paper). The laminates contain from 0% to 50% of paper. Young's moduli and breaking strengths of the unoriented holocellulose paper laminates can be theoretically predicted from the properties of their constituents using laws of mixtures. The mechanical properties of the Whatman paper laminates are significantly higher than those predicted from the laws of mixtures. This indicates that the polymer increases the strength of the fiber-to-fiber bonds of the weaker sheets, although it does not change the bond strength of a stronger paper such as the holocellulose paper. For the oriented paper laminates, changes in Young's modulus with angle of measurement are explained by the composite material theories if the angular variations in shear modulus are taken in to account. Changes in breaking strength with angle for the oriented laminates can be analyzed by Tsai and Azzi's theory for composite materials.

Mechanical characterization of untreated waste office paper/woven jute fabric hybrid reinforced epoxy composites

“…It is to be noted the positive role played by the addition of paper sheets in jute reinforced composites: this is apparent when comparing the performances of the hybrid composites, which showed the highest flexural and tensile moduli. An increase in mechanical properties due to the addition of paper sheets was also found by Prud'Homme,15 resulting in a significant reinforcement of a PMMA matrix. As regards the flexural behavior, it can be noted that better performances are obtained when the paper sheets are placed as skins in the hybrid composites.…”

“…Several authors have investigated the properties and processing of recycled newspaper fibres as a possible reinforcement for thermoset14, 15 and thermoplastic polymer matrix16–20 and the need of using various coupling agents to improve the interaction and the interface fibre‐matrix owing to the incompatibility between the hydrophilic fibres and the hydrophobic polymers 21–29…”

“…In contrast, the literature on exploitation of waste untreated paper sheet forms is rather limited 15, 30…”

“…In fact, whilst Yadav30 et al investigated the mechanical and water uptake properties of waste newspaper reinforced phenolic‐epoxy matrix composites using waste newspaper sheets (at various weight fractions from 0.30 to 0.65) directly in the matrix without any pretreatment, Prud'homme15 studied laminates of oriented and unoriented holocellulose paper, and of Whatman filter paper.…”

Etude des proprietes du polystyrene en solution en fonction des conditions de polymerisation

“…Le problkme de la correction a apporter aux paramktres obtenus, pour tenir compte de la polydispersiti des Cchantillons, prend ividemment beaucoup 11 semble bien que la loi caractirisant la polydispersiti du polystyrhe obtenu par voie radicalaire soit sensiblement indipendante de la tempirature de polymerisation, du moins de 0°C a 60°C.…”