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As one of the most abundant natural polymers in nature, polysaccharides have the potential to replace petroleum-based polymers that are difficult to degrade in paper coatings. Polysaccharide molecules have a large number of hydroxyl groups that can bind strongly with paper fibers through hydrogen bonds. Chemical modification can also effectively improve the mechanical, barrier, and hydrophobic properties of polysaccharide-based coating layers and thus can further improve the related properties of coated paper. Polysaccharides can also give paper additional functional properties by dispersing and adhering functional fillers, e.g., conductive particles, catalytic particles or antimicrobial chemicals, onto paper surface. Based on these, this paper reviews the application of natural polysaccharides, such as cellulose, hemicellulose, starch, chitosan, and sodium alginate, and their derivatives in paper coatings. This paper analyzes the improvements and influences of chemical structures and properties of polysaccharides on the mechanical, barrier, and hydrophobic properties of coated paper. This paper also summarizes the researches where polysaccharides are used as the adhesives to adhere inorganic or functional fillers onto paper surface to endow paper with great surface properties or special functions such as conductivity, catalytic, antibiotic, and fluorescence.

The main objective of the present work was to carry out a small theoretical practical investigation on the comparison of the adhesive Aquazol® with the present adhesives:starch and Thylose® in the technique of paper lamination that proves the effectiveness of this adhesive, as a suitable product in the lamination process, observing the data obtained in the test specimens, for its reversibility, its easy application, the change of perception and the resistance to the adhesive joint. In order to reach this goal, a bibliographic search was initially made about the different adhesives regarding the method of manual paper lamination and the different application systems. Beginning with this information, a wide variety of materials and systems were selected to carry out paper lamination tests. Fot this, a total of three adhesives, an application system and a single type of secondary support -Japanese paper- were chosen, resulting in a total of 15 different laminations. In order to compare the results that could be obtained from the different adhesives, it was decides to perform a peeling test in T. Once the tests were completed, a comparison of results was carried out along with conclusions of the advantages and disadvantages of the different adhesives and the method used, attaching summaries and visually explanatory graphs., El objetivo principal del presente trabajo era realizar una pequeña investigación teórico práctica sobre la comparación del adhesivo Aquazol® con los adhesivos actuales: almidón y Thylose® en la técnica de laminación de papel que demuestre la eficacia de este adhesivo, como un producto apto en el proceso de laminación, observando los datos obtenidos en las probetas, tanto por su reversibilidad, su fácil aplicación, el cambio de percepción y la resistencia a la junta adhesiva. Para poder llegar a tal fin, inicialmente se realizó una búsqueda bibliográfica sobre los diferentes adhesivos en el método de laminación manual de papel y los diferentes métodos de laminación manual del papel y sistemas de aplicación de los mismos. A partir de esta información, se eligieron diversos materiales y sistemas para llevar a cabo las pruebas de laminación de documentos de papel. Para ello se escogieron un total de tres adhesivos, un sistema de aplicación y un solo tipo de soporte secundario -papel japonés- de los que resultaron un total de 15 laminaciones distintas. Para poder comparar los resultados que se pueden obtener de los diferentes adhesivos, se decidió realizar una prueba de pelado en T. Una vez finalizadas las pruebas, se realizó una comparativa de resultados y unas conclusiones de las ventajas y desventajas de los diferentes adhesivos y el método empleado, adjuntando resúmenes y gráficos visualmente explicativos.

We demonstrate the use of patterned aerosol adhesives to construct both planar and nonplanar 3D paper microfluidic devices. By spraying an aerosol adhesive through a metal stencil, the overall amount of adhesive used in assembling paper microfluidic devices can be significantly reduced. We show on a simple 4-layer planar paper microfluidic device that the optimal adhesive application technique and device construction style depends heavily on desired performance characteristics. By moderately increasing the overall area of a device, it is possible to dramatically decrease the wicking time and increase device success rates while also reducing the amount of adhesive required to keep the device together. Such adhesive application also causes the adhesive to form semi-permanent bonds instead of permanent bonds between paper layers, enabling single-use devices to be non-destructively disassembled after use. Nonplanar 3D origami devices also benefit from the semi-permanent bonds during folding, as it reduces the likelihood that unrelated faces may accidently stick together. Like planar devices, nonplanar structures see reduced wicking times with patterned adhesive application vs uniformly applied adhesive.

SUMMARY Objective To evaluate, through the application of different dentin bonding systems, the influence of wetness on shear bond strength in enamel. Methods This study evaluated three etch-and-rinse adhesive systems (Scotchbond MP [used with and without primer]; Singlebond; and Prime&Bond 2.1) and two self-etching adhesive systems (Clearfil SE Bond; and Xeno IV). Flat bovine enamel surfaces were either air-dried for 30 seconds or blotted with absorbent paper after acid-etching for the conventional bonding agents or before the application of self-etching bonding agents. The resin composite EsthetX was bonded to flat surfaces that had been treated with one of the adhesives, following the manufacturer's instructions. After being stored in water at 37°C for one week, bonded specimens were broken in shear. Data were evaluated with two-way analysis of variance (ANOVA) and Student-Newman-Keuls tests (α=0.05). For comparing each condition individually, regardless of the adhesive or wetness condition, a one-way ANOVA and a Student-Newman-Keuls test (α=0.05) were applied. Results The two-way ANOVA showed significant differences among adhesive systems. An interaction effect was also observed (p Conclusion The all-in-one adhesive behaved differently depending on whether the enamel surface was dry or wet.

Enzymatic bonding methods, based on laccase or peroxidase enzymes, for lignocellulosic products such as medium-density fiberboard and particleboard are discussed with reference to the increasing costs of presently used petroleum-based adhesives and the health concerns associated with formaldehyde emissions from current composite products. One approach is to improve the self-bonding properties of the particles by oxidation of their surface lignin before they are fabricated into boards. Another method involves using enzymatically pre-treated lignins as adhesives for boards and laminates. The application of this technology to achieve wet strength characteristics in paper is also reviewed.

Short carbon fibers (SCF) were modified with oxidation and coupling treatment to improve their water-wettability and bonding properties. Four types of dispersants were studied and discussed. Short carbon fibers/plant fiber (PF) composite papers were prepared by papermaking techniques. Scanning electron microscopy (SEM) and tests to determine zeta potential, absorbance, tensile index, and conductivity were carried out to investigate the modified effect of SCF and the interfacial properties. Modification experimental results showed that the surface grooves were deepened and new superficial grooves were generated by the liquid acid oxidation. The reaction with the silane coupling agent provided higher density and more uniform distribution on the SCF surface than that of organic titanate, and it obviously increased the roughness and the absolute value of zeta potential. After modification, the hydrophilic properties and dispersion in aqueous solutions were improved, the SCFs could form a good mechanical grip with plant fibers, and the conductivity and physical strength of SCF/PF composite papers were enhanced. It was shown that there was obvious adhesive binding at the fiber overlap nodes by the SEM analysis. It was confirmed that the improvement of physical properties of composite paper can be ascribed to the interfacial enhancement.

Mechanical abrasion is an extremely simple, rapid, and low-cost method for deposition of carbon-based materials onto a substrate. However, the method is limited in throughput, precision, and surface compatibility for drawing conductive pathways. Selective patterning of surfaces using laser-etching can facilitate substantial improvements to address these current limitations for the abrasive deposition of carbon-based materials. This study demonstrates the successful on-demand fabrication of fully-drawn chemical sensors on a wide variety of substrates (e.g., weighing paper, polymethyl methacrylate, silicon, and adhesive tape) using single-walled carbon nanotubes (SWCNTs) as sensing materials and graphite as electrodes. Mechanical mixing of SWCNTs with solid or liquid selectors yields sensors that can detect and discriminate parts-per-million (ppm) quantities of various nitrogen-containing vapors (pyridine, aniline, triethylamine)., United States. Army Research Office. Institute for Soldier Nanotechnologies, United States. Defense Advanced Research Projects Agency, National Institutes of Health (U.S.) (Ruth L. Kirschstein National Research Service Award F32CA157197), National Cancer Institute (U.S.)

An off-the-shelf, moisture-responsive, acetate- backed adhesive tape is investigated as a commercially avail- able smart material for fabricating low-cost, multifunctional, humidity-responsive millimeter-scale structures. Laser ablation is used for cutting and thinning-down the tape to enhance its response. Water-submerged cantilevers show a radius of cur- vature of 3 mm or lower (for laser-thinned cantilevers). Addi- tionally, their humidity response is a function of the angle between the longitudinal axis of the cantilever and polymer orientation. A cut angled at 80 � with respect to this orientation results in a tip rotation of up to 25 � , enabling the formation of bending cantilevers with twisting behavior. The tape cantile- vers are further functionalized with magnetic nanoparticles and used to create four-finger grippers that close underwater within minutes and can sample 100 mL of liquid. A cyclic humidity monitor is also fabricated using a tape strip that walks unidir- ectionally on a ratchet-shaped surface upon exposure to humidity variations. V C 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2013, 51, 1263-1267

Multifunctional integration is an inherent characteristic for biological materials with multiscale structures. Learning from nature is an effective approach for scientists and engineers to construct multifunctional materials. In nature, mollusks (abalone), mussels, and the lotus have evolved different and optimized solutions to survive. Here, bio-inspired multifunctional graphene composite paper was fabricated in situ through the fusion of the different biological solutions from nacre (brick-and-mortar structure), mussel adhesive protein (adhesive property and reducing character), and the lotus leaf (self-cleaning effect). Owing to the special properties (self-polymerization, reduction, and adhesion), dopamine could be simultaneously used as a reducing agent for graphene oxide and as an adhesive, similar to the mortar in nacre, to crosslink the adjacent graphene. The resultant nacre-like graphene paper exhibited stable superhydrophobicity, self-cleaning, anti-corrosion, and remarkable mechanical properties underwater.

We describe a latex wet coalescence method for gas-phase immobilization of microorganisms on paper which does not require drying for adhesion. This method reduces drying stresses to the microbes. It is applicable for microorganisms that do not tolerate desiccation stress during latex drying even in the presence of carbohydrates. Small surface area, 10–65 μm thick coatings were generated on chromatography paper strips and placed in the head-space of vertical sealed tubes containing liquid to hydrate the paper. These gas-phase microbial coatings hydrated by liquid in the paper pore space demonstrated absorption or evolution of H2, CO, CO2 or O2. The microbial products produced, ethanol and acetate, diffuse into the hydrated paper pores and accumulate in the liquid at the bottom of the tube. The paper provides hydration to the back side of the coating and also separates the biocatalyst from the products. Coating reactivity was demonstrated for Chlamydomonas reinhardtii CC124, which consumed CO2 and produced 10.2 ± 0.2 mmol O2 m−2 h−1, Rhodopseudomonas palustris CGA009, which consumed acetate and produced 0.47 ± 0.04 mmol H2 m−2 h−1, Clostridium ljungdahlii OTA1, which consumed 6 mmol CO m−2 h−1, and Synechococcus sp. PCC7002, which consumed CO2 and produced 5.00 ± 0.25 mmol O2 m−2 h−1. Coating thickness and microstructure were related to microbe size as determined by digital micrometry, profilometry, and confocal microscopy. The immobilization of different microorganisms in thin adhesive films in the gas phase demonstrates the utility of this method for evaluating genetically optimized microorganisms for gas absorption and gas evolution.

Major commercial bookbinding technique used today is perfect binding (or adhesive binding), originally used for paperback books. In perfect binding, adhesive is used to attach the pages of a book together and attach the book cover. One of most important criterion for adhesive binding is strength over the whole length of a book leaf. It is known that adhesion strength is function of the bond between the leaf and adhesive and total sum of material contact area. The subjects of research are physical properties of paper that have impact on different general sources of binding strength. The tests were performed with constant parameters of binding process and two chemically different types of paper.

We report a simple, low-cost and detachable microfluidic chip incorporating easily accessible paper, glass slides or other polymer films as the chip materials along with adhesive wax as the recycling bonding material. We use a laser to cut through the paper or film to form patterns and then sandwich the paper and film between glass sheets or polymer membranes. The hot-melt adhesive wax can realize bridge bonding between various materials, for example, paper, polymethylmethacrylate (PMMA) film, glass sheets, or metal plate. The bonding process is reversible and the wax is reusable through a melting and cooling process. With this process, a three-dimensional (3D) microfluidic chip is achievable by vacuating and venting the chip in a hot-water bath. To study the biocompatibility and applicability of the wax-based microfluidic chip, we tested the PCR compatibility with the chip materials first. Then we applied the wax-paper based microfluidic chip to HeLa cell electroporation (EP). Subsequently, a prototype of a 5-layer 3D chip was fabricated by multilayer wax bonding. To check the sealing ability and the durability of the chip, green fluorescence protein (GFP) recombinant Escherichia coli (E. coli) bacteria were cultured, with which the chemotaxis of E. coli was studied in order to determine the influence of antibiotic ciprofloxacin concentration on the E. coli migration.