Search

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.

In this experiment, we use corn starch as the main raw material and use Mid-Temperature a-amylase to modifie it. The influnce of temperature and time to viscosity of the enzymatic starch were discussed. In this way, we can get the optimal conditions about enzymatic modification. According to testing properties of the paper ,we know about its surface sizing effect. At last,we explored the influnce of AKD to surface sizing. The results showed that the optimal conditions are as follows: the optimal enzyme reaction temperature of 65 °C and the ptimal enzyme reaction time of 20min under the condition that the substrate concentration of 20%, the dosage of enzyme of 0.02%, the dosage of calcium chloride of 0.04%, pH 6, gelatinization temperature of 95 °C, and gelatinization concentration of 10%.Under this condition, the viscosity of starch paste is 11mPas. Compared with original paper, sizing increased by 16.20%, burst index increased by 10.50%, tensile index increased by 12.60%. The AKD can significantly improve the degree of sizing, compared with the original paper, the degree of sizing increased by 26.5%.

With the development of world's paper industry, strength agent has become increasingly wide spread and more important.This paper describes a method for modified APMP with Chitosan, we make studies on using chitson to improve the properties of paper, and compare the effect of them based on experimential results. As a result of study,it can be concluded: The pH value and the dosage of chitosan have a great influence on the physical strength of paper.When the pH was 6 and the dosage of chitosan was 1%,the tensile index of paper could reach 30% above.

initiator is one of the most important conditions of synthesizing efficient strength agent CPAM. To begin with initiating mechanism, three redox systems of acrylamide aqueous polymerization (NH4)2S2O8/ Na2 SO3, K2S2O8/NaHSO3 and K2S2O8/Na2 S2O4 have been studied. The effects of different kinds of initiator, initiator concentration, and monomer concentration as well as polymerization temperature on relative molecular weight and strength effects of CPAM have been investigated. K2S2O8/Na2 SO3 is the most useful system in synthesizing efficient strength agents.

Aluminium silicate fiber is an excellent high-temperature material which is widely used in special paper industry in recent years. Due to its property of hardly interweave into the paper and the low strength of the single inorganic fibers paper, it is difficult to make a general basis weight paper. In response to these issues, the strength of the paper was improved by adding some plant fibers. This study takes advantage of good resistance to high temperature of inorganic adhesive and bonding capacity of organic intensifier. Meanwhile two inorganic adhesives (waterglass and ludox) and one organic adhesives carboxymethy starch (CMS) were used in the process of preparing the aluminium silicate paper. The physical properties and insulation properties of the paper which prepared from the difference conditions were studied. The experiment results showed that the adhesive of waterglass and ludox can improve the properties of resistant to high temperature. The adding dosages were 10% and 7.5ml, respectively. The best ratio of alumina silicate fiber to conifier fiber is 7 to 3.The using of CMS can decrease the amount of the plant fiber and its best usage is 10%.

The stickies in pulp and paper machinery especially in the blankets will cause a lot of problems such as paper defects, increasing the time of machine shut down . Therefore, Inhibiting the Stickies of blanket is very important to regular production. In this study,we mainly studied on the inhibition of Stickies in the blanket with enzyme. The processed blanket was treated by several kinds of enzymes. The results showed that the optimum enzyme treatment conditions were obtained as followings:PH of 7, temperature of 50°C, 2×104U/g of cellulose enzyme, 2×103U/g of amylase and 104U/g of lipase. The blankets obtained better cleaning situation under this conditions.

Sepiolite has good adsorptivity due to their high surface area and structural channels. During the process of making aluminium silicate fiber paper, inorganic binders retaintion was little because of the smooth surface of aluminium silicate fibers. In this study, sepiolite was used to improve tensile strength of the sheet by increasing inorganic binders retaintion rate through its high adsorptivity. The effect of sepiolite on the tensile strength of alimunium silicate fiber paper was investigated. The results showed that the best mass ratio of aluminium silicate fibers to spiolite was 7:3. Under this condition, the tensile strength of the sheet was 4.79 N•m/g, which increased by 24.2% from the one without sepiolite.

In this paper, we proposed the method to synthesize the modified polyamide polyamine enhancer, which takes PAE, styrene and acrylic as raw materials. Factors that would affect the preparation of the modified polyamide polyamine enhancer, such as monomer amount, reaction time, initiator amount and emulsion concentration, were discussed in detail. Experimental results showed that the modified polyamide polyamine enhancer achieved optimum effect the strength of tube roll base paper under the conditions: the amount of acrylic is 6%, the ratio of styrene and PAE is 2:1, holding time 4h, and the amount of initiator 0.7%. The modified polyamide polyamine enhancer applied to tube roll base paper. The optimum amount of modified polyamide enhancer was 1%. The ring crush strength of paper prepared in this condition can be increased by 44% and the stiffness can be increased by 46%.

PAE as the wet strength agent has a long history; it not only has the wet strength performance and the retention and drainage characteristics. This paper focuses on the technological conditions of preparation of PAE wet-strength agent and the application conditions. The results showed that the well PPC was obtained under the following conditions: the mole ratio of adipic acid and diethylenetriamine were 1:1.05, the amount of catalyst (mole ratio of the total raw materials) was 1%, the temperature of heat preservation was 165°C and the reaction time was 4h. The optimum condition of preparing PAE was obtained as followings: the ratio of EPI to PPC of 1.2:1, the epoxidation temperature of 60°C and reaction time of 2h. While applied in softwood pulp, when the dosage of PAE was 1%, the wet strength agent provided the satisfactory effect.

In this paper, the effect of microwave treatment on the hydrogen peroxide bleaching of Soda-AQ wheat-straw pulp was investigated. The results showed that microwave treatment could increase the brightness of the hydrogen peroxide bleached pulp. The fiber coarseness of microwave enhancing peroxide bleached pulp was higher than that of the peroxide bleached pulp. However, the arithmetic average fiber length, the length weighted average fiber length and weight weighted average fiber length of the former was lower than that of the latter. Fourier transform infra-red spectroscopy (FTIR) and X-ray diffraction (XRD) spectra showed that CrI(%) crystallinity of microwave enhancing peroxide bleached pulp was similar as that of the peroxide bleached pulp but all higher than that of the Soda-AQ wheat-straw pulp. N·O′KI infra-red crystalline index of microwave enhancing peroxide bleached pulp were lower than that of the peroxide bleached pulp. The FTIR spectra of lignin showed that the microwave treatment had some influences on the methoxyl and phenolic group in lignin.

In this paper, Water glass and sulfuric acid were used as raw materials to do the synthesis of hydrated silica by the method of precipitation, and then hydrated silica is applied in paper coating. By examining the changes of the coated paper’s various properties to study the effects of different reaction conditions to the final products. And then we obtained a optimal synthesis conditions: sulfuric acid concentration 25%, reaction time 50min, reaction temperature 80°C, sodium silicate modulus 2.8, stirring speed 150r/min, the relative amount of sodium sulfate content compared to SiO2 is 25% .And at last the outward appearance of the hydrated silica and the structural changes in paper coating were observed by scanning electron microscopy.

The preparation of alumina silicate refractory fiberboard by wet vacuum filter molding process, alumina silicate fibre is the matrix material, and high-temperature resistance adhesive is the agglutinant. Experiments made in conditions of no liquid glue, and not adding fiber, influence of cycling time on liquid glue concentration, density of fiberboard, and retention of cementing compound was studied; effect of density of fiberboard on thermal conductivity is also discussed. The results showed that the optimum liquid glue concentration is 9.41%, cycling time is 28h (replenish liquid glue after 28h). Density of alumina silicate fiberboard is 289kg/m3, and alumina silicate fiberboard can resistance to 1200 °C.