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The paper adopts modified carbon fiber with Meldrum's acid and silane coupling agent (KH-550), then add the modified carbon fiber to the paper based friction materials. The paper aims to explore the changes of modified carbon fiber in its surface structure and properties by electron microscopy and infrared spectral analysis, and the effect of anionic microparticle forming retention aid system comprised of lithium soapstone-cationic polyacrylamide (CPAM) on mechanical properties and retention of paper based friction materials. Compared with the addition of unmodified carbon fiber to paper based friction materials, the addition of modified carbon fiber with Meldrum's acid, silane coupling agent, Meldrum's acid and silane coupling agent enhance the tensile strength of paper based friction materials. The tensile index of paper based friction materials was separately enhanced by 64.87 %, 91.38 % and 28.88 %. Compared with the paper based friction materials without the anionic microparticle forming retention aid system, the basis weight of paper based friction materials increased by 13.97 %.

By changing ther factors of synthesis process of PAE, discussed the effects of synthetic conditions on the PAE curing, and through electron microscope analysis methods, the curing mechanism of PAE is preliminary discussed.When the ratio of DTEA/AA was 1:1.05,the dry and wet strength of paper before and after curing achieved the best value.when the dosage of p-toluene sulfonic acid is 1.5%, the PAE can achieve best effect.the best ratio of PPC and epichlorohydrin is 1:0.7.

To enhance the effectiveness of polyvinyl alcohol (PVA) coated fertilizers, a novel slow-release fertilizer was developed using biochar and waterborne copolymer of PVA and polyvinylpyrrolidone (PVP) as coating materials. The effects of botanical origins and doses of biochar as well as copolymer concentrations on biochar-copolymer structures and properties were investigated. Our results indicated that the water absorbency of blend films differing in biochar origins showed different responses to these three factors. Generally, biochar decreased water absorbency of copolymer with an increased degradability, and contributed to improving the slow-release property of coated urea. In particular, rice biochar-based copolymer (S5 film) had less hydrophilic OH bonds and encapsulated urea granules more compactly and densely. The urea particles coated with rice biochar-based copolymer (S5 film) exhibited an excellent release behavior of 65.28% nutrient leaching on the 22th day. Therefore, this work has demonstrated the potential of biochar-based copolymer from different botanical biochar for improving the effectiveness of fertilizers.

In this research, the urea-formaldehyde prepolymer and multilayer hot-press drying was used to obtain modified wood. The timbers were compressed and dried by the multilayer hot-press drying kiln. The combination of chemical modification and hot-press drying can improve the drying rate, which can also enhanced the physical and mechanical properties. Based on the findings, the basic density of modified wood improved 25.2 %, the bending strength and the bend elastic modulus improved 15.6 % and 25.0 % respectively. The dimensional stability of the treatment appeared to be slightly higher than that of untreated samples under the same conditions for processing temperatures and times. The improving dimensional stability of wood mainly was attributed to the prepolymer that changes wood cell wall components such as the degradation of the hemicelluloses and cellulose during hot-press drying treatment. The XRD results indicated that the degree of crystallinity increased to 35.45 %from 31.25 %. The TGA results show that the degradation of the samples can be divided into two step, both of the maximum weight loss velocity temperature of the two step increased to 266 °C, 355 °C from 244 °C and 341 °C.

A preparation method of Urea-formaldehyde performed polymer(UFP) with low molecular weight and high reactivity is presented. The UFP can impregnate into wood along trachea from the ends with pressurized impregnation method. In the following heating and pressing processes of the wood, the UFP polymerizes, and it enhances stability and strength of the wood. The impregnating-pressing-drying method avoiding the disadvantage of dealing with the large specimens using vaccum-pressing method is suitable for industrial production. Results from test showed the degree of crystallinity tested by XRD were 30%, 32% in different dosage of the modifier. Utilizing a combination of low molecular weight resin impregnation and pressing resulted in a density increase of UFP treated wood from 0.214 to 0.268g/cm3. At the same time, the Young’s modulus and bending strength increased from 1.407GPa to 1.759GPa and 64MPa to 74.5MPa, respectively. But the formaldehyde emission is great reduced from 0.5% to 0.008%. It can be concluded that the effective utilization of UFP impregnated in wood is a promising technique for the production of high-strength in the drying and pressing processing.