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Microfibrillated cellulose (MFC) was prepared from the bleached kraft hardwood pulp using TEMPO/NaClO/NaBr oxidation system and high pressure homogenization. By changing dosages of the TEMPO, NaClO and NaBr, the pressure and times of homogenization, pretreatment and homogenization process were optimized. Experimental investigation indicated that for making MFC of high quality, 0.25%TEMPO, 2.5%NaBr, 60%NaClO (based on oven dry pulp), 20 times of homogenization, pressure of 60MPa in the process of treatment were required. At last, the mechanical and barrier properties were tested after the base paper was coated by homemade MFC. The study suggested that mechanical properties (especially 5 times increase of the folding strength) increased substantially and air permeability decreased by 100times.

The influence of coating layer structure on both physical and printing quality of the paper was studied. Different coating layers were obtained by changing the ratio of polyvinyl alcohol adhesives and silicon dioxide pigments in the coating formula. Then the structure, physical properties and ink-jet printing performance of the coated paper were measured. The influences of coating structure on physical properties and ink-jet printing performance were evaluated. The results showed that as the ratio of adhesive increased, the coating porosity decreased; the average pore diameter increased at first and then decreased, but in general tended to decrease; the initial drop contact angle increased, which testified the stronger hydrophobicity of the coated surface with higher adhesive ratio. The average pore diameter has a negative linear correlation with paper roughness while has a positive linear correlation with air permeability. The larger the average pore diameter, the greater the density values, as well as the better tone reproduction and the larger color gamut range. Average pore diameter also has a weak correlation with dot area and dot roundness.

This paper describes the use of a printing circuit technology to generate hydrophilic channels in a filter paper. Pattern was first designed using Protel soft, and printed on a blank paper. Then, the pattern was transferred on a sheet copper using a thermal transfer printer. The sheet copper with pattern was dipped in a ferric trichloride solution to etch the whole pattern of the sheet copper. At last, the etched sheet copper was coated with paraffin, then with a filter paper and heated at the other side of the sheet copper with an electric iron. The melting paraffin penetrated full thickness of the filter paper and formed a hydrophobic “wall”. Colorimetric assays for the presence of protein and glucose were demonstrated in the paper-based device. The work is helpful for researching paper-based microfluidic devices for monitoring health and detecting disease.

The waste corrugated paper was grinded to paper pulp first, and then the paper pulp was used to prepare the foamed waste paper pulp/high density polyethylene（HDPE）composites by compression molding with HDPE. The Rosand double-barrel capillary rhepmeter was used to research the influences of the blowing agent AC(Azodicarbonamide) content，waste paper pulp content，temperature and different blowing agent on the melt of the composites. Scanning electron microscopy（SEM）was also used to observe the effects of different contents of AC and waste paper pulp on the cell morphologies.The results showed that: when the shear rate up to 600 S-1，the melt performs of the foamed waste paper pulp/ HDPE composites were pseudoplastic flow, and turn up wall slip phenomenon. The viscosity of melt was significantly reduced with the content of AC increased, but it increased with the content of the waste paper pulp increased. When the shear rate reduced to 275 S-1 or below, the viscosity of melt reduced as the temperature riased; while when the shear rate went up to 275 S-1 or high, the viscosity of melt increased as the temperature riased. When the shear rate reduced to 325 S-1 or below, the melt of endothermic blowing agent （NaHCO3）showed the highest viscosity; when the shear rate went up to 325 S-1 or high, the melt of exothermic blowing agent AC shows the highest viscosity. The number of cell increased and size of cell became smaller with the AC content increased , but the number of cell reduced and the size of cell became larger with the content of waste paper pulp increased observing by SEM.

This paper draws on a roll coating method which used for the production of coated paper. Polylactide coating cardboard was prepared through the solvent coating, and study its packaging performance. In this study, chloroform is based solvent, ethanol or n-propanol as auxiliary solvents, poly (ethylene glycol) or poly caprolactone as plasticizer, and the water vapor permeability, oxygen permeability and heat sealability of polylactic acid coated cardboard.

It is usually reported that chitosan is used as paper strengthening agent. However, it is sorry that the study choosing chitosan which DD (degree of de-acetyl )and viscosity is filtered by experiments is blank. Many chitosan samples of wide viscosity range and wide DD range were tested by their strengthening effect on bleched wheat straw pulp. Then a few sample of chitosan is selected because of their obvious strengthening effect on pulp. This study could be as the foundation of further research of chitosan used as paper strengthening agent.

Biocomposites sheets were prepared by compression molding from mixtures of corn starch plasticized by glycerol as matrix and cellulose fibers, extracted from used office paper, as reinforcement filler with contents ranging from 0 to 8% wt/wt of fibers to matrix. Properties of composites were determined by mechanical tensile test, differential scanning calorimetry, thermogravimetric analysis, water absorption measurement, and scanning electron microscopy. The results showed that higher fibers content raised the tensile strength and elastic modulus up to 109% and 112%, respectively, when compared to the non-reinforced thermoplastic starch (TPS). The addition of the fibers improved the thermal resistance and decreased the water absorption up to 63.6%. Scanning electron microscopy illustrated a good adhesion between matrix and fibers.

The novel flexible pressure sensor with skin-like stretchability and sensibility has attracted tremendous attention in academic and industrial world in recent years. And it also has demonstrated great potential in the applications of electronic skin and wearable devices. It is significant and challenging to develop a highly sensitive flexible pressure sensor with a simple, low energy consuming and low cost method. In this paper, the silver nanowires (AgNWs) as electrode material were synthesized by polyol process. The polydimethylsiloxane (PDMS) was chosen as a flexible substrate and polyimide (PI) film as dielectric layer. The AgNWs based electrode was prepared in two methods. One is coating the AgNWs on photographic paper followed by in situ PDMS curing. Another one is suction filtration of the AgNWs suspension followed by glass slide transfer and PDMS curing. Then the capacitive pressure sensor was packaged in a sandwich structure with two face to face electrodes and a PI film in the middle. The sensitivity of the sensor as well as the micro-structure of the electrodes was compared and studied. The results indicate that the roughness of the electrode based on AgNWs/PDMS micro-structure plays an important role in the sensitivity of sensor. The as-prepared flexible pressure sensor demonstrates high sensitivity of 0.65kPa-1. In addition, the fabrication method is simple, low energy consuming and low cost, which has great potential in the detection of pulse, heart rate, sound vibration and other tiny pressure.

Langmuir-Blodgett technique was applied to build optically homogeneous film of functionalized multi-walled carbon nanotubes (MWCNTs) on paper substrate. The palladium (Pd) nanoparticles were drop-casted onto MWCNTs network films before being exposed in hydrogen (H2) gas molecules environment under vacuum and atmospheric pressure at room temperature. The results demonstrate that the functionalized MWCNTs dispersed with Pd nanoparticles show good H2sensing response on paper substrate where the sensitivity of around 10 % was recorded at only 2 minutes exposure time.

Magnetic stripe cards and magnetic recording paper are commonly used in credit cards, identity cards, and transportation tickets. Barium ferrite was used to prepare magnetic inks and the magnetic ink was coated onto the paper substrate to obtain the magnetic papers. The crystal structure of barium ferrite was characterized by X-ray diffraction (XRD) and the magnetic property of barium ferrite was tested by vibrating sample magnetometer (VSM) The performance of the magnetic recording paper and the surface morphology of the coating magnetic layer were also characterized. The results show that the magnetic ink based on barium ferrite with the formula of 41wt% of the barium ferrite powder, 14wt% of polyurethane, 36wt% of solvent and 9wt% of PVP has good printing characteristics and the magnetic recording papers have good performance.

In order to investigate the influence of coating layer characteristics on the dynamic permeability and printing of ink-jet paper, coating was prepared by the precipitated calcium carbonate (PCC) and white latex used as bottom coating (recipe label:A,B),and coating formula was made by silica (SiO2) and polyvinyl alcohol used as surface coating (recipe label:a,b,c).Then paper were coated respectively on single bottom, single surface and multilayer. Then the dynamic permeability and printing of ink-jet paper were analyzed systematically. The results showed that whether single layer or multilayer, the values of Ct, Ci were minimum when the ration of pigment and adhesive was 70:30, because the hole diameter of the coating layer was smallest, and the absorption was strongest, so the dynamic permeability was best, and the ability of ink absorption was best, color density and tone reproducibility were best. It concluded that when the proportion of SiO2 and PVA was 70:30, the dynamic permeability and printing ability of ink-jet paper were relative better.

The bonding mechanism between water-based UV curable ink and active groups on paper’s fiber during curing process was studied in this paper. Low viscosity water-based UV-cured resin was synthesized by epoxy resins, epoxy diluent, acrylic acid and maleic anhydride in the presence of catalyst. The viscosity of the synthesis system and synthetic products were significantly reduced when epoxy diluent was added to replace parts of the epoxy resin. Epoxy diluent was very useful in reducing the viscosity of the product, but over-dose would have negative effects on the quality of the cured film. The water-based epoxy acrylate prepolymer was used as the substitution for the ink to investigate the binding mechanism between the active groups of prepolymer and fiber under UV irradiation. The prepolymer and photoinitiator were mixed and the mixture was diluted to an appropriate viscosity by a small amount of water, then printed on the paper by the method of analog printing and curred by UV curing machine. The printed paper was used to extract lignin by enzymatic/mild acidolysis. FT-IR was used to characterize the changes of the active groups in lignin. The results showed that the changes of active groups in lignin were founded in the existence of ultraviolet and photoinitiator, which consistent with the change of double bonds in prepolymer. The free radicals produced by photoinitiator in curing process not only promoted the double bonds to polymerize, but also accelerated the active groups of lignin binding. Experiments show that chemical bonds exist between them.

The composite SiOx/polymer films are deposited as a top-coatings onto the paper substrates by radio frequency (RF) reactive magnetron co-sputtered two targets, silica and dicyclopentadiene dioxide cured with maleic anhydride (DCPD/MA).The samples prepared by changing PSiO2/PDCPD/MA, the ratio of RF powers density delivered to the individual target from 0.1 to 10 so as to prepare different SiOxcontent coatings. The wettability, mechanical properties, color reproduction printability, chemical characterization of the coatings are discussed in this paper, using contact angle measurements, electronic tensile testing machine, off-set printing test and FTIR. The static contact angle of water ranges from 129.7 to 90.7 o and tensile performance has improved significantly as the ratio of RF powers density change from 0.1 to 10. The ink density and depth of color during off-set printing are visually improved by using papers with hydrophobic surfaces coated composite films.

A novel method of direct aniline multi-interfacial polymerization on paper substrate is introduced in this paper. Cellulose base papers with and without PAE reinforced were discussed. The PANI-paper composites after more than 3 polymerizations had much lower surface resistivity. Their mechanical strength and thermal stability were analyzed by tensile test and GTA. FTIR results explained that there was strong interaction between NH groups in aniline monomers and OH groups in fibers. Conductive composites made with PAE treated paper had both good thermal stability and good mechanical strength with high conductivity.

The X-ray diffraction of hydrated calcium silicate is analyzed and is applied in papermaking. It shows that hydrated calcium silicate have certain crystalline state. The tensile strength, tearing strength and folding strength of paper decrease in different degree with the increase of dosage of hydrated calcium silicate while the whiteness and the printing color density of paper improve. T tensile strength and folding strength of paper decrease in varying degrees with the increase of dosage of PAM while the tearing strength of paper and the whiteness improve. And the printing color density of paper is the same.

Screen printing fluorescent security inks can be widely applied in the field of anti-counterfeiting packaging and printing special. Paper-based screen printing fluorescence security ink was prepared by europium polymer fluorescent material as fluorescent agent, alkyd resin etc as links, meanwhile various additives were added. The performance of europium polymer was studied by IR, UV spectra, fluorescence spectra, and fluorescent security performance of ink were studied by fluorescence spectrophotometer, the results showed that the fluorescence emission spectrum was narrow, and had a main peak at 612nm and high fluorescence efficiency, so this ink had good fluorescence security performance. The fineness,viscosity,stability etc printability of the ink were studied by fineness gauge, viscosity meter, the test result showed that the ink had good printability, can be applied in the security printing process of screen printing.

Humidity control paper board comprising natural polymer derivatives, porous natural minerals, inorganic salts, natural moisturizing material and paper was prepared by simple physical blending and its humidity control properties were tested. The moisture adsorption and desorption rate are 0.82 g/7h.g-1 and 0.71 g/7h.g-1, respectively. The adsorbed moisture amount is 0.85 g/g. It can maintain the relative humidity (RH) range between 50% and 60% within 20 min at 25 °C. Above all, the prepared paper board shows pronounced humidity control properties and the preparation technology is simple, which is feasible for production in large scale.

In order to improve the physical and color laser printing properties of paper, the polyvinyl alcohol and silica were used for pigmental surface sizing of paper. Under the previous conditions of solid content 12% and 14%, the effects of different ratio of PVA and silica such as 100:0, 15:1, 10:1, 5:1, and 1:1 on the physical properties of paper and laser printing performance were investigated. The brightness, opacity, roughness, color density, gray scale and image definition were measured after the surface sizing paper was calendared under the condition of temperature 70°C and pressure 4MPa. When the solid content was 12%, PVA: SiO2 was 1:1 and the solid content was 14%, PVA:SiO2 was 10:1, the brightness and opacity of paper obtained the maximum values. With the increase of silica proportion roughness increased at first and then decreased. Color density and tone reproducibility of paper was significantly improved by the pigmental sizing treatment as well as the dots and lines definition. The reasonable pigmental sizing scheme was as follow: solid content was 12%, PVA:SiO2 was 1:1, sizing temperature was 60°C, calendar temperature was 70°C and calendar pressure was 4MPa.

Mica paper is made as one kind of insulation material, but low strength limits its applications. Surface modification is proved to be an effective way to enhance its strength. In this paper modifier like ethylene diamine tetraacetic acid, cationic polyacrylamide, cationic starch, ethylene diamine tetraacetic acid plus cationic polyacrylamide and ethylene diamine tetraacetic acid plus cationic starch are introduced to improve strengths of mica paper. Finally ethylene diamine tetraacetic acid plus cationic starch is chosen as modifier of mica flakes. After modification mica paper can reach high tensile strength of 19.84N/cm, which is more than six times high than mica paper without any modification.

As a high technique environmental friendly material, Wood-plastic composite (WPC) material has wide range of applications and is extruded by recycled wood fiber products and wasted LDPE. Waste Paper-Al-Plastic materials including Tetrapak beverage and milk boxes are used to extrude the WPC as thermal insulation exterior wallboard instead of normal wood fiber material in the present research. In this paper, simulated thermal insulation and Oxygen index combustion test were operated at the Lab conditions. Some experimental results are presented as follow: heat transfer coefficient of 100mm thick WPC hollow wall is 0.922 W/m2•K, which is equivalent to the thermal insulation performance of a 0.35m thick fly ash aerated concrete block. Oxygen index of 27 indicates that WPC is inflammable material. Zinc borate (ZB) and ammonium polyphosphate (APP) are effective flame retardant for Paper-Al-Plastic WPC.