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In order to improve the strength properties of high filler filled papers, a new technique of coating starch on the clay surface was developed. The stability of the coated starch and its effects on paper properties were studied. It was found that the starch coated on the clay surface swelled in water. This swelled starch film on the filler surface contributes significantly to the filler–filler bonding. The strength properties of handsheets made from starch coated clay, even with unmodified corn starch, could be increased by more than 15% versus those from the traditional method of adding cationic or amphoteric potato starch directly to 50% bleached softwood pulp/50% bleached hardwood pulp. This research suggests that the starch coated filler can be used to make high filler content paper products. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 44–50, 2005

Chitosan coatings prominently improved both the gloss and oxygen barrier properties of paper. The gloss value in the machine direction was increased as a function of added chitosan. An oxygen-permeability value of 1.1 cm3/m2 d was obtained when 6.9 g/m2 chitosan was applied to 80 g/m2 copy paper. In addition, the effects on the mechanical properties were positive, but not significant. The water-vapor permeability of the paper increased as a result of the chitosan coating. Chitosan dissolved in 1.6, 3.2, and 6.4% lactic acid showed antimicrobial activity against Bacillus subtilis, whereas acetic and propionic acids (1.6, 3.2, and 6.4%) did not produce any notable activity. Nisin (0.08 g/L) did not enhance the antimicrobial activity of coatings prepared from chitosan dissolved in different acids. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 986–993, 2004

Recycling waste paper can be considered as a means to displace the use of natural cellulose fibers applied in building materials, because it is composed mostly of cellulose. The water absorption and special surface area of cellulose fibers are the key properties for their use in building materials. The objective of this article was to study the production of recycled cellulose fibers from waste paper using ultrasonic wave processing. The physical and chemical properties of recycled cellulose fibers, such as water absorption, specific surface area and pore characteristics, etc., were investigated with various testing methods. The results indicated that the ultrasonic cavitation effect was feasible for the preparation of the secondary fibers. When the ultrasonic treatment time lasted for 10 min, the water absorptions of both newsprint fibers and kraft fibers increased significantly and reached the highest values of 12.5 g/g and 11.2 g/g, respectively, which were nearly two times than that of fibers without ultrasonic treatment. With a pretreatment of 20 min, the average length and fineness of recycled cellulose fibers decreased by 4% and 25%, respectively, and the length-diameter ratio of the recycled cellulose fibers was 1.28 times than that of the untreated fibers, which greatly increased the special surface area of the recycled cellulose fibers. This work also determined that NaOH was useful to improve the physical properties of the recycled cellulose fibers. Because the recycled cellulose fibers after processing, fulfilled several technical indexes, they can be considered as a filling material for used in cement-based materials. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41962.

Fluorescein silica nanoparticles (NPs) were prepared using a silane compound bound between fluorescein-N-hydroxysuccinimide (NHS-Fluorescein) and 3-aminopropylorthosilicate by a sol–gel method. The fluorescein-silica NPs were mixed with a poly(vinylidene fluoride) (PVDF) solution, and the solution loaded with the NPs was electrospun on a filter paper. Scanning electron microscopy and transmission electron microscopy images confirmed the encapsulation of the fluorescein silica NPs in the PVDF nanofibers. Laser scanning confocal microscopy (LSCM) images showed fluorescein silica NPs as dots, and photoluminescence (PL) images obtained using a fluoroanalyzer indicated the emission of uniform PL from filter papers coated with fluorescein-silica-NP-encapsulated PVDF nanofibers. It was demonstrated that the fluorescein silica NPs enabled PVDF nanofibers coated on a filter paper to be easily visualized. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45125.

Polycarboxylic acids have been used as crosslinking agents for wood pulp cellulose for improving paper wet strength. Our previous research showed that low-molecular-weight polymeric carboxylic acids are effective in improving paper wet strength retention and reducing its flexibility. In this research, we compared two polymeric carboxylic acids, that is, poly(maleic acid) (PMA) with Mn of 800 and poly(methyl vinyl ether-co-maleic acid) (PMMA) with Mn of 1,130,000 for improving paper wet strength. The kraft paper sheets were treated at a 2% acid level and cured at different temperatures. The dry strength, wet strength, and folding endurance of the treated sheets were measured. We found that PMA and PMMA have comparable effectiveness in improving paper wet strength and wet stiffness. However, the treatment with PMA increases paper brittleness and severely diminishes paper folding endurance, whereas the treatment with PMMA increases both the dry strength and folding endurance by enhancing the paper's toughness. This striking difference in the performance of the treated paper is attributed to the different nature of the crosslinkages formed on the sheets. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 74: 907–912, 1999

Kraft paper was coated with resins based on vegetable oils and then tested for mechanical properties, rate of biodegradation in soil, and ability to inhibit weed growth. Resins included oxidatively polymerized linseed oil (LO) and a polyester formed by the reaction of epoxidized soybean oil and citric acid (ESO-CA). Tensile strength of LO-coated paper (82 MPa) was slightly higher than uncoated paper (68 MPa), while the tensile strength of ESO-CA coated paper was somewhat lower (45 MPa). Elongations to break (3- 8%) were similar for all samples. The rates of weight loss and tensile strength during soil burial decreased as follows: uncoated paper . LO coated paper . ESO-CA coated paper. The polymerized oils acted as barriers to penetration of microorganisms to the cellulosic fibers. Resin-coated papers inhibited weed growth for . 10 weeks, while uncoated paper was highly degraded and ineffective by 6 -9 weeks. © 1999 John Wiley & Sons, Inc.* J Appl Polym Sci 73: 2159 -2167, 1999

The binary nanocomposites of poly lactic acid (PLA) with the montmorillonite modified with trisilanol polyhedral oligomeric silsesquioxanes (Trisilanolisooctyl POSS®) were prepared via a solution-blending process and coated on paper by bar coating and compress hot melt coating methods. The resulting components were characterized with Fourier transform infrared spectroscopy, and X-ray diffraction (XRD) techniques. Moreover, the water vapor transmission rates (WVTR) for the coated writing paper were determined using an IGA-003. The results indicated that the modified clay PLA nanocomposites enhanced the water vapor barrier properties of coated paper significantly. The permeability of PLA nanocomposites to water vapor decreased by 74% [26.0 g/(m2 day)], respectively, as compared to those of the paper coated with pure PLA. The dispersion and phase behavior of the modified montmorillonite in PLA matrix was revealed by Transmission electron microscope. The intercalation of montmorillonite with PLA was further demonstrated using XRD. WVTR results indicated that the compress hot melt coating of the nanocomposites is an effective method to improve the water vapor resistance of coated paper. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40952.

Development of thin, flexible, light-weight, renewable, low-cost, and environmentally friendly electrode materials are highly feasible in era of modern disposable electronic technology. This article presents the synthesis and dielectric studies of polypyrrole (PPy) coated pulp fibers, directly collected from wasted egg holder's tray. PPy coated pulp fibers converted into compact sheet for the development of potential renewable and low-cost electrode materials. The morphology, chemical structure, and thermal stability of naked and PPy coated pulp fibril sheets were investigated by scanning electron microscopy (SEM), Fourier transform infrared (FTIR) and thermogravimetric analysis (TGA), respectively. PPy coated pulp fibers revealed better thermal stability and compactness of sheet morphology. Impedance measurements showed a high value of dielectric constant of 1.15 × 106 at 0.5 Hz and conductivity of 7.45 × 10−4 S/cm at room temperature for PPy coated pulp fibril sheet. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42422.

Microcapsules composed of waste paper fibers and plastics were prepared by semichemical recycle method. Newspaper and expanded polystyrene (EPS) for packing electric appliances were used as the raw materials of paper fiber (FB) and plastics, respectively. In this experiment, fibers were treated with a few surface treating agents prior to the encapsulation operation in order to improve the dispersability in the nonaqueous liquid phase and then in the shell of microcapsules. Microcapsules prepared thus were found to be of single-cored type. Furthermore, it was found that the mechanical strength of microcapsules was increased by addition of fibers and there were the optimum concentrations of the surface treating agents. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 80: 2662–2669, 2001

The chemical components of cellulosic insulation (i.e., Kraft paper, cellulose, lignin, pentosans) used in electrical transformers were aged in transformer oil to determine the relative yield of furanic degradation products. The results show that the pentosans component of the paper give, by far, the highest yield of 2-furfural followed by cellulose, levoglucosan, and lignin. However, the pentosans did not produce any detectable quantities of either 5-hydroxymethyl-2-furfuraldehyde or 2-furfurol, both of which are known to be produced by the degradation of Kraft paper. α-Cellulose was found to give 3 times as much 2-furfural as levoglucosan, which is a degradation product of cellulose, suggesting another pathway to 2-furfural production from cellulose than exclusively through the commonly quoted mechanism in which levoglucosan is the intermediate. It was also found that the production of 2-furfural from levoglucosan appears to be accelerated by acidic conditions in oxidized oil. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 69: 2541–2547, 1998

The disposal of paper mill sludge (PMS) is a difficult environmental problem. Thus, PMS has been used as a substitute for wood fiber (WF) to reinforce high-density polyethylene (HDPE). In this study, we compared PMS–WF–HDPE composites with composites without PMS after water immersion and thermal treatment. Water immersion and thermal treatment were conducted at 25 and 70°C, respectively. The results show that the composites with PMS absorbed less water but lost more of their original flexural properties after immersion; thereby, their strength was compromised. These reduced mechanical properties could be partially restored after redrying. After the thermotreatment, the composites with added PMS lost their weight and flexural properties, whereas the composites without PMS gained flexural strength. The results show that the thermotreatment improved the impact strength of the composites when no more than one-third of WF was replaced with PMS. Fourier transform infrared spectroscopy and energy-dispersive X-ray energy-dispersive spectroscopy showed that the wood index of the PMS composite decreased more than the index of the non-PMS composite, whereas the carbonyl index increased more. However, the PMS composite showed a lower increase in the total oxygen/carbon weight ratio. This study suggested that limited amounts of WF could be substituted with PMS to reinforce HDPE. However, WF–PMS–HDPE composites should not be used in hot, humid environments for long periods. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41655.

International audience; An array of highly conductive, lightweight and flexible cellulose nanopapers as effective attenuators of electromagnetic radiations within 8.2–12.4 GHz (X band) were formulated via in situ polymerization of pyrrole monomers on to cellulose nanofibers (CNFs). It is quite obvious that the free hydroxyl groups on the surface of CNFs facilitate the formation of intense intermolecular hydrogen bonding with PPy which is envisaged for its excellent electromagnetic shielding performance with an average shielding effectiveness of ca. –22 dB (>99% attenuation) at 8.2 GHz for a paper having 1 mm thickness. The fabricated papers displayed a predominant absorption mechanism (ca. 89%) rather than reflection (ca. 11%) for efficiently attenuating electromagnetic radiations, which has a considerable importance in the modern telecommunication sector. Thus, the designed PPy/CNF papers would replace the conventional metal‐based shields and pave way for the development of green microwave attenuators functioning via a strong absorption mechanism. The PPy/CNF nanopapers exhibited a DC conductivity of 0.21 S/cm, a prime requisite for the development of highly efficient electromagnetic shields. Undoubtedly, such nanopapers can be employed in wide range of applications such as electrodes for supercapacitors and other freestanding flexible paper‐based devices.

The finish obtainable on coated paper depends on the materials used as well as the way in which it is calendered. The rheological properties of the coated mixtures revealed the difference between them. When the apparent viscosity, η, was calculated and plotted against the shear rate, y, on a log-log graph, an approximate linear relations were obtained. On the other hand, a plot is drawn between the shear rate and shear stress, in which a hysteresis loop is obtained connecting the up and down curves. It is clear from these plotting, that the rheological properties for the prepared coating mixtures show time-dependent behavior, because they are share rate dependence, and they can form sol-gel character. Moreover, the pigments used in the coating mixture were usually chosen because of their different impacts on coating color properties and also on the properties of the coating layer. Therefore, one can use the coating mixture to have higher optical properties and to improve the permeability of the sheets.

Stand-up pouches are one of the fastest growing packaging concepts, which are replacing the traditional packaging formats. In this study, stand-up pouch prototypes are prepared from cellulose fatty acid coated heat-sealed virgin kraft paper with leak proof seals. This study demonstrates that molar mass controlled cellulose ester (C6-C16) coatings can significantly improve the barrier properties of virgin kraft paper. All cellulose ester coatings performed better compared to that of PLA. Cellulose ester coatings also improved the resistance of virgin kraft paper against tested nonpolar oil and grease compounds. In addition, the cellulose ester coatings had no antimicrobial activity, and fewer microbes adhered to them than to the PLA surface. The results demonstrate that cellulose fatty acid ester coatings have high potential in future applications requiring good barrier properties.

Poly(carboxylic acid)s have been used as crosslinking agents for wood pulp cellulose to increase the wet strength of paper. In this research, we evaluated the effects of two multifunctional carboxylic acids, i.e., 1,2,3,4-butanetetracarboxylic acid (BTCA) and poly(maleic acid) (PMA), on the wet strength retention, dimensional stability, wet stiffness, and folding endurance of the treated paper. We observed that the wet strength retention, dimensional stability, and wet stiffness of the treated sheets increase, whereas the folding endurance decreases as the poly(carboxylic acid) concentration applied to those sheets increases. We measured the ester carbonyl band absorbance in the spectra of the treated paper. The linear correlation between the ester carbonyl band absorbance and wet strength, dimensional stability, and wet stiffness indicates that the improvement in the wet performance of the treated paper is directly attributed to the ester crosslinking of the wood pulp cellulose by poly(carboxylic acid)s. The data presented in this article also indicate that FTIR spectroscopy can be used for predicting the performance of the paper crosslinked by poly(carboxylic acid)s. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 67: 649–658, 1998

The effect of press-drying temperature on the surface chemistry of chimicothernomechanical pulp fibers has been studied using electron spectroscopy for chemical analysis (ESCA). The chemical composition showed no significant variation for press-dried samples at temperatures between 25 and 140°C. On the other hand, ESCA showed that lignin content increased whereas hemicelluloses content decreased on the surface of press-dried samples at 175°C. By its hydrophobic nature, lignin gives to paper and paperboards better dimensional stability and resistance to moisture and water. However, lignin does not intervene in fiber bonding because the specific bond strength does not vary with press-drying temperature. © 1996 John Wiley & Sons, Inc.

A composite sandwich structure, consisting of a paper sheet as a middle layer and two porous coating layers of a highly filled acrylate–styrene–butadiene copolymer, has been studied by means of a dynamic mechanical test in torsion. Stiffness and mechanical damping, tan δ, were recorded over the temperature region where the latex polymer exhibits a glass transition. The mechanical damping decreases with increasing filler content in the coating. Variations in the thickness of the coating layers did not influence the mechanical damping. The glass transition temperature of the latex polymer increases with increasing volume fraction of filler at high filler contents as an effect of filler–matrix interaction. The outer layers partly penetrate into the middle layer, as indicated by thickness measurements on the coated paper. A theoretical comparison of the peak heights of the mechanical damping using lamination theory shows a discrepancy in the experimental results. If penetration of the outer layer is allowed for, i.e., if using a thicker outer layer of the composite in the calculations, a favorable correlation between the theoretical and the experimental results is obtained. © 1993 John Wiley & Sons, Inc.

Leather industry generates large amounts of wastes, most of them are burned causing environmental pollution. This study aims to use these wastes as filler in bagasse pulp before sheet formation, as a novel method. Leather shavings were subjected to multistage disintegration to prepare powder, then treated with different monomers and applied in paper sheets. The formed sheets exhibit a considerable improvement in some of their properties such as tear, water resistance, air permeability, and thermal stability. Only breaking length was affected by adding untreated and treated leather shavings. Consequently, the resulting paper sheets have potential for application in wrapping and packaging industries. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010

Polyurethane–urea microcapsules were prepared by an interfacial polymerization method. Dynamic mechanical measurements were carried out on the polyurethane–urea microcapsules coated on a paper substrate. The glass transition temperatures (Tg) of capsule wall were observed in the temperature scan data. Tg as the temperatures of tan δ peaks were decreased with increasing amounts of core materials. The apparent activation energies of the glass transition were estimated at about 100 kcal/mol. Master curves were obtained by shifting the tan δ spectra along the frequency axis, and the glass transition regions were unaffected by core materials studied. The shift factors were found to depend on the core/wall ratio and discussed in terms of a morphological change of microcapsules. © 1994 John Wiley & Sons, Inc.