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• 72% − 80% of fibre was recovered from disposable coffee cups. • 2% and 3% consistency shredded cups required > 100 kWh/tonne to repulp with 3 refiner passes. • Pulp quality did not significantly diminish after repulping using a single-disk refiner. Over 64 billion paper-plastic laminate (PPL) coffee cups are consumed between the United States and Canada annually, the majority accumulating in landfills due to a hydrophobic plastic inner-lining. Recycling can mitigate environmental damage and provide economic value from repurposed products. We found that standard repulping methods were insufficient to separate fiber from plastic due to the low intensity of treatment. To increase process intensity, we mechanically refined shredded PPL coffee cups and Kraft eucalyptus sheets (control) at 2%, 3%, and 4% consistencies with three passes to determine the energy required to separate fibers from plastic and the effects on fiber quality. 2% and 3% consistency PPL cups measured under 40 kWh/tonne of input material for one refiner pass and ∼ 80 kWh/tonne for 4% consistency PPL cups. Recovered fiber fraction totaled 87.7%, 85.3%, and 80.5% of input mass of Kraft eucalyptus and 72.3%, 72.6%, and 79.6% of input mass of PPL cups at 2%, 3%, and 4% consistency, respectively. Fines content of PPL cups jumped from 8% pre-refining to ∼ 30% post-refining while Kraft eucalyptus fibers were unaffected, suggesting that breaking the plastic-fiber bonds results in fines generation. Mean fiber length of PPL cups slightly decreased with consistency and tensile strength improved. Freeness decreased with consistency only in PPL cup samples. These results demonstrate a low energy requirement to effectively separate fiber and plastics in PPL cups as well as minimal impact on fiber quality using existing refining technology, and provides an estimate of the financial costs of local recycling efforts. [ABSTRACT FROM AUTHOR]

Heat sealing behavior of mono‐polyolefins and paper‐based materials is drastically different from conventional multilayer plastic laminates. This paper presents the effect of sealing conditions on Hot‐Tack and Cold‐Tack for an oriented polypropylene (OPP)‐based polyolefin laminate with either polyethylene (PE) or cast polypropylene (CPP) sealing layer and two different barrier paper materials carrying a thin acrylic copolymer sealing layer. The investigations include pressure, temperature, time, jaw pattern, and climate conditions (moisture). It is shown that the mono‐polyolefins reach comparable Hot‐Tack and Cold‐Tack ranges compared with the reference polyethylene terephthalate (PET)‐aluminum (Al)‐PE laminate. The CPP laminate exhibits a narrow sealing window near the range in which shrinkage is observed. While for the polyolefins temperature plays the main role, the sealing of paper materials turned out to be dependent on pressure, time, and moisture content in paper. Due to a rupture through the polymer thin coating, the Cold‐Tack is dominated by a delamination of paper and coating. Consequently, the Cold‐Tack is drastically lower than with PET‐Al‐PE laminate. Monopolypropylene films exhibit extremely narrow sealing window, which shall be taken into the design consideration of bag form‐fill‐seal (FFS) machines. Polymer coated paper can be potentially used at high‐speed FFS; however, special attention shall be paid to moisture content control and filling. [ABSTRACT FROM AUTHOR]

In paper containing multilayer composite structures and laminates, polarization is usually investigated under dry environmental conditions. The aim of this research is to determine polarization dependence of paper and paper-dielectric structures on environmental relative humidity (RH). The role of each component was identified. The obtained and recorded data are used for identification and clarification of the physical mechanism of polarization. The polarization was studied by applying a dosed charging and forced discharge method and was evaluated by a depolarization potential and its formation kinetics. The polarization level of investigated structures increases with RH and is determined mainly by the paper (cellulose) and moisture content in it. In composite structures of the paper between dielectric films and dielectric on paper the polarization dependence on RH correlates with moisture absorption isotherm. It was found that the surface electrical conductivity of paper distorts the results of the paper and structure paper on dielectric. Analysis of the formation kinetics of the depolarization potential together with the potential decay of the charged paper has determined the role of orientation polarization and space charges. The formation of space charges is faster than orientation polarization and dominates in polarization process at higher RH. The process modeling by superposition of two exponents confirms this polarization mechanism. [ABSTRACT FROM AUTHOR]

Thermal and catalytic pyrolysis of aluminum plastic laminate over zeolite catalysts were performed to produce high quality oil. Thermogravimetric analysis of aluminum plastic laminate indicated that the decomposition kinetics of aluminum plastic laminate were changed by interactions between the polymer components during the thermogravimetric analysis of aluminum plastic laminate. The effects of aluminum foil on the aluminum plastic laminate decomposition kinetics were negligible. The catalytic pyrolysis of aluminum plastic laminate over the acid catalysts using tandem-micro reactor-gas chromatography/mass spectrometry produced large amounts of aromatics due to the properties of the main polymers, polyethylene and poly (ethylene terephthalate), in aluminum plastic laminate. Among three catalysts, HZSM-5 (SiO 2 /Al 2 O 3 , 23), HY(30), and Al-MCM-41 (20), HZSM-5 (23) had the highest efficiency on aromatics production followed by HY(30) and Al-MCM-41 (20). Co-feeding aluminum plastic laminate to the catalytic pyrolysis of paper over HZSM-5 (23) and HY(30) was also effective on aromatics production, highlighting the potential use of aluminum plastic laminate to enhance the synergistic aromatics formation during the catalytic pyrolysis of biomass. • Interaction between polymers changed kinetic behavior of aluminum plastic laminate. • Catalytic pyrolysis of aluminum plastic laminate produced aromatics efficiently. • HZSM-5 was the most effective catalyst on aromatics formation. • Co-feeding aluminum plastic laminate and paper produced additional aromatics. [ABSTRACT FROM AUTHOR]

We describe a low cost optical temperature sensor that is simple to manufacture. The sensor is constructed by simple soaking of paper in a solution of the temperature sensitive luminescent indicator Ru(phen) 3 and subsequent lamination of the dried paper. Lamination prevents O 2 diffusion to the indicator and thus eliminates O 2 cross-sensitivity. The temperature sensitivity was up to −2% change in luminescence lifetime per K, a t 90 response time of 10 s. Besides luminescence lifetime based measurements, the sensor is well suited for ratiometric imaging with simple RGB cameras, where the temperature dependent red luminescence can be referenced by the blue luminescence of the optical brightener in the paper. [ABSTRACT FROM AUTHOR]

Paper and prints on it are analyzed as composite materials. Printing, varnishing and lamination are described in terms of the formation of the composite material. The article discusses why and how the properties of a print should differ from the properties of paper. [ABSTRACT FROM AUTHOR]

The effect of plant-fiber paper or silver nanowires-loaded paper interleaves on the electrical conductivity and interlaminar fracture toughness of composites was studied. Highly conductive paper was prepared by surface-loaded silver nanowires. The percolation threshold appeared at about 0.4 g/m2. The surface resistivity reached 2.3 Ω/sq when the areal density of silver nanowires was 0.95 g/m2. After interleaving the conductive papers in the composite interlayers, in-plane electrical conductivity perpendicular to the fiber direction was increased by 171 times and conductivity through thickness direction was increased by 2.81 times. However, Mode I and Mode II interlaminar fracture toughness decreased by 67.3% and 66.9%, respectively. Microscopic analysis showed that the improvement of conductivity was attributable to the formation of an electrical conducting network of silver nanowires which played a role in electrical connection of carbon fiber plies and the interleaving layers. However, the density of the highly packed flat plant fibers impeded the infiltration of resin. The parallel distribution of flat fibers to the carbon plies, and poor resin-fiber interface made the interlaminar fracture occur mainly at the interface of plant fibers and resin inside the interleaves, resulting in a decline of the interlaminar fracture toughness. The surface-loading of silver nanowires further impeded the infiltration of resin in the densely packed plant fibers, resulting in further decline of the fracture toughness. [ABSTRACT FROM AUTHOR]