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Cellulose-based materials represent a renewable, biodegradable, and environmentally friendly alternative to plastic from fossil resources. Nanopaper is a strong and lightweight material formed from cellulose nanofibrils (CNFs). Paper and nanopaper have been considered as excellent alternatives to plastics for use in agriculture and for packaging applications. However, common for both paper and nanopaper is their hydrophilic character, and consequently, poor water-resistance properties. ORMOCER®s are a class of inorganic–organic polymers with excellent barrier and protective properties used for a range of coating applications. Here we present ORMOCER®-coated paper and nanopaper. The coated papers and nanopapers are characterized, both in terms of their morphology, hydrophobicity, and mechanical properties. We demonstrate that the pressure used during the pressing and drying of paper and nanopaper influence their tear and tensile—properties, and that the morphology of the coated nanopaper differs significantly from that of the coated paper. While the ORMOCER® was impregnated within the porous network of the paper, a well-defined two-layered morphology was obtained with the coated nanopaper. Further, the biodegradability of the nanopaper with and without coating was assessed. The degradation study demonstrated that both the pressure used during the pressing and drying of the nanopaper, and the composition of the ORMOCER®, influenced the rate of degradation. Taken together, ORMOCER®-coated paper and nanopaper are promising for the preparation of materials that are both water-resistant, renewable, and biodegradable. [ABSTRACT FROM AUTHOR]

Information on industrial paper obtained from special purpose heat-resistant and fire-resistant fibers by the method of fiber swelling is presented. Results of a study of the effect of fiber cutting length on the mechanical properties the paper are presented. Corresponding dependencies are established. [ABSTRACT FROM AUTHOR]

Information is provided on the properties of technical-purpose papers based on heat-resistant superhigh modulus (SHM) para-aramid fibres containing heterocyclic rings. Various methods of producing such papers are reviewed. The properties of samples of the heat-resistant papers are listed. The results of study and comparison of chemical resistance of the obtained papers are adduced. [ABSTRACT FROM AUTHOR]

There is a continuing demand for bio-sustainable and readily recyclable polymers for hot food packaging and hot beverage containers. An important candidate for these applications is poly(lactic acid), PLA, which possesses insufficient heat deflection temperature (HDT) performance, short of being fully crystallized. In order to address this issue, correlations were established for the observed enhancement in HDT with PLA resin after annealing with both thermal properties and the crystallinity of PLA (Ingeo™ 4032D) and extrusion melt blends thereof. The kinetic parameters of crystallization (reaction order, n and rate constant, k (s)) were obtained after fitting the Avrami equation. The reaction order for all of the systems had an n of approximately 3. Models derived from the Avrami equation with n ~ 3 are consistent with systems that undergo heterogeneous nucleation and subsequent spherulitic crystal growth. The addition of paper and talc did not change the model but did change the rate of crystallization. An increased quantity of cellulosic filler led to an increased rate of crystallization. The smaller particle sized fillers offered the greatest improvement in the rate of crystallization. However, the smaller-sized inorganic fillers did not appear to further improve HDT above that of the annealed blends of PLA/paper. The melting temperature for the PLA and all of the blends thereof formed containing paper from different sources of talc had identical melting temperatures ( T ). The variations in the HDTs of the composites were not found to be mirrored in the T . Annealing typically raised the crystallinity from approximately 10-15 to 30-40%. In situ determinations of enhanced moduli via annealing were performed using solid torsion bar dynamic mechanical spectroscopy, the results of which support the findings obtained via DSC. The annealed PLA/paper blends were found to be superior overall to the PLA/talc blends and are, importantly, sustainable. [ABSTRACT FROM AUTHOR]

In museums, libraries and archives, some of the paper relics, upon ageing, are very brittle and even cannot be handled without destroying the material. This is because of the depolymerization of cellulose and, consequently, the loss of mechanical strength. To prolong the life expectancy of paper relics, the poly(methyl methacrylate- co-butyl acrylate- co-styrene) (MMA-BA-ST) was used to strengthen the fragile paper fibers in this work. The relation between the mass concentration of MMA-BA-ST emulsion and the specific properties of papers (e.g., folding endurance, tensile strength, tearing strength, whiteness and glossiness) and the ageing resistance were investigated. In addition, the effect of MMA-BA-ST on different types of paper was also studied. Furthermore, the reinforcing mechanism of MMA-BA-ST on paper was also investigated by dissipative particle dynamics simulations. The results showed that MMA-BA-ST could significantly improve the mechanical properties and ageing resistance of papers. [ABSTRACT FROM AUTHOR]

The preparation of microfibrillar cellulose (MFC) films by filtration on a polyamide filter cloth, in a dynamic sheet former and as a surface layer on base paper is described. Experimental evidence of the high tensile strength, density and elongation of films formed by MFC is given. Typically, a MFC film with basis weight 35 g/m2 had tensile index 146 ± 18 Nm/g and elongation 8.6 ± 1.6%. The E modulus (17.5 ± 1.0 GPa) of a film composed of randomly oriented fibrils was comparable to values for cellulose fibres with a fibril angle of 50°. The strength of the films formed in the dynamic sheet former was comparable to the strength of the MFC films prepared by filtration. The use of MFC as surface layer (0–8% of total basis weight) on base paper increased the strength of the paper sheets significantly and reduced their air permeability dramatically. FEG-SEM images indicated that the MFC layer reduced sheet porosity, i.e. the dense structure formed by the fibrils resulted in superior barrier properties. Oxygen transmission rates (OTR) as low as 17 ml m−2 day−1 were obtained for films prepared from pure MFC. This result fulfils the requirements for oxygen transmission rate in modified atmosphere packaging. [ABSTRACT FROM AUTHOR]

The basic types of polymer composite materials (PCMM) made from different kinds of reinforcing fibre fillers: short-cut fibres, paper, yarns, tow, sliver, fabrics, and nonwovens, and their properties and use are examined. Information on the fabrication and properties of the different kinds of composites are reported: extruded fibre plastics, getinaxes, textolites, unidirectional composites, honeycomb plastics, and others. New kinds of composites with ultrahigh mechanical and thermal characteristics are also examined. Some of the reported information was previously covered very sparely in the literature. Based on the examination, the features of polymer fibre composites are summarized in comparison to other materials, and they can be summarized as the following basic points: 1) combining different kinds of fibre fillers and matrices (binders) allows fabricating PCM with a wide range of properties by selecting the optimum indexes for articles with a broad spectrum of applications; 2) articles made of fibre PCM are not very materials-intensive and are technologically effective for processing in comparison to many traditional materials, metals and ceramics in particular; 3) with respect to the specific mass characteristics, fibre PCM can be many times superior to articles made of traditional materials—metals, etc., so that the mass (weight) characteristics of articles made of fibre composites can be significantly reduced, which is especially important for using them in vehicles, aircraft, rescue equipment, and sporting goods; 4) articles made of composites have high performance reliability, are almost immune to corrosion, and do not require special protection or periodic painting of the surface. Due to the features of the properties and use, fibre PCM have a great future in the most varied areas of application. [ABSTRACT FROM AUTHOR]

Extrusion coating experiments were carried out in the pilot line at Tampere University of Technology (Institute of Paper Converting). Commercially produced 3-hydroxybutyrate/3-hydroxyvalerate copolymer, commercial Finnish paper, and paperboard qualities were utilized as substrates. Functional properties, such as heat-sealing and hot-tack properties, pinhole density, and water vapor transmission rate were determined. PHB/V coatings exhibited approximately four–six times higher water vapor transmission rates (WVTR) than the corresponding LDPE coatings. The incorporation of wax or tall oil rosin into PHB/V improved its water vapor barrier. Curling of PHB/V was reduced by the addition of wax or tall oil rosin into the base polymer. PHB/V provided good heat-sealing characteristics at rather high sealing temperatures. Pinhole density was substantially reduced by using higher molecular weight PHB/V and by incorporating plasticizer into PHB/V. [ABSTRACT FROM AUTHOR]