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Application of Colloidal Chemistry and Polymer Chemistry in Papermaking Industry
Issue:
Volume 8, Issue 1, March 2022
Pages:
1-6
Received:
16 January 2022
Accepted:
28 January 2022
Published:
9 February 2022
Abstract: Colloidal chemistry is a science to study the physicochemical properties of generalized colloidal dispersion systems. Polymer chemistry is a new comprehensive subject that studies the synthesis, chemical reaction, physical chemistry, physics, processing and application of polymer compounds. The development of polymer chemistry mainly experienced four periods: the utilization and processing of natural polymers, the modification of natural polymers, the production of synthetic polymers and the establishment of polymer science. Since the 1930s, with the development of synthetic polymers, polymer related sub disciplines such as reaction kinetics, chemical thermodynamics, structural chemistry, polymer physics and biopolymers have been gradually established, forming a systematic polymer science. Papermaking industry is an industrial sector that manufactures all kinds of paper and paperboard. It includes the pulp manufacturing industry that uses wood, reed, bagasse, straw, wheat straw, cotton straw, hemp stalk, cotton and other raw materials to manufacture pulp, the paper and paperboard industry, and the processing paper manufacturing industry that produces coated, polished, glued, laminated and other processing paper and font paper plate. Paper industry is an important industry closely related to the development of national economy and the construction of social civilization. This paper focuses on the relationship between colloidal chemistry, polymer chemistry and papermaking industry, especially its application in cooking, washing, bleaching, papermaking and water treatment, and introduces in detail the current situation and development trend of flocculation method for papermaking wastewater according to colloidal chemistry theory.
Abstract: Colloidal chemistry is a science to study the physicochemical properties of generalized colloidal dispersion systems. Polymer chemistry is a new comprehensive subject that studies the synthesis, chemical reaction, physical chemistry, physics, processing and application of polymer compounds. The development of polymer chemistry mainly experienced fo...
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Application of Colloid Theory in Urea Formaldehyde Resin
Issue:
Volume 8, Issue 1, March 2022
Pages:
7-10
Received:
16 January 2022
Accepted:
28 January 2022
Published:
9 February 2022
Abstract: Urea formaldehyde resin is an end-stage thermosetting resin in which urea and formaldehyde are polycondensated into an initial urea formaldehyde resin under the action of alkaline or acidic catalyst, and then an insoluble and non-fusible resin is formed under the action of curing agent or additives. Urea formaldehyde resin has the characteristics of colorless curing adhesive layer, good operation performance, low cost, good bonding performance and water resistance. Its use in the field of wood bonding is increasing. The cured urea formaldehyde resin is lighter in color than phenolic resin, translucent, resistant to weak acid and alkali, good insulation, excellent wear resistance and low price. However, urea formaldehyde resin is easy to decompose in case of strong acid and alkali, and its weather resistance is poor. There is a problem of formaldehyde emission in the manufacturing and use of wood-based panels produced by urea formaldehyde resin, so it must be modified. At present, urea formaldehyde resin is the largest adhesive used in wood industry, especially in the manufacture of various wood-based panels in wood processing industry, urea formaldehyde resin and its modified products account for about 90% of the total amount of adhesive. In this paper, the development and application of colloidal theory in urea formaldehyde resin are introduced, and the significance and Prospect of this theory are prospected.
Abstract: Urea formaldehyde resin is an end-stage thermosetting resin in which urea and formaldehyde are polycondensated into an initial urea formaldehyde resin under the action of alkaline or acidic catalyst, and then an insoluble and non-fusible resin is formed under the action of curing agent or additives. Urea formaldehyde resin has the characteristics o...
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Jute Stick- A Suitable and Economical Source as Charcoal and Activated Carbon Preparation
Shuranjan Sarkar,
Zakaria Ahmed
Issue:
Volume 8, Issue 1, March 2022
Pages:
11-15
Received:
17 January 2022
Accepted:
7 February 2022
Published:
16 February 2022
Abstract: Charcoal is a light-weight black carbon residue produced by strongly heating wood with minimal oxygen to remove all water and volatile constituents. Jute sticks were used as a cheap precursor for the preparation of charcoal and activated carbon. Chemical activation with CaCl2 caused the physicochemical changes in charcoal. Jute sticks were carbonized at a range of 250°C to 750°C temperatures by an electric muffle furnace where 40–45% higher yields were observed at 250°C temperature and yields declined (8–10%) with an increase in temperature up to 500°C. In the case of charcoal, the average moisture was 9.88%. The IR results of charcoal analysis were indicated 3,450 cm-1 for the moisture and 1689.34 cm-1 for carboxyl groups. Ash was obtained at a temperature of 550°C in thermogravimetric analysis. At the first phase (50–340°C) of activated carbon, moisture was released (24% weight loss) because of the activation of activated carbon, which consumes more water than charcoal. The oxidation of carbon occurred in the range of 340–550°C and the remaining 1% of inorganic materials became ash. Food and beverage processing, snow avalanche control, municipal drinking water, industrial pollution control, radio wave capture, methane solvent recovery, odor remover, metal purification, and sewage treatment will all benefit from this activated carbon. The properties of the final materials obtained after pyrolyzing at 700°C can be a suitable approach.
Abstract: Charcoal is a light-weight black carbon residue produced by strongly heating wood with minimal oxygen to remove all water and volatile constituents. Jute sticks were used as a cheap precursor for the preparation of charcoal and activated carbon. Chemical activation with CaCl2 caused the physicochemical changes in charcoal. Jute sticks were carboniz...
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Effect of Curing Agent Dosage on Fire Resistance of Waterborne Epoxy Coating
Jingying Wang,
Rongrong Zheng,
Xingwei Li,
Hongjing Liu,
Liyan Wang
Issue:
Volume 8, Issue 1, March 2022
Pages:
16-20
Received:
22 February 2022
Accepted:
10 March 2022
Published:
18 March 2022
Abstract: The water-based epoxy fire retardant coating is formed by reaction curing, which not only has good anti-corrosion performance, but also has environmental protection and flame retardant performance, which is suitable for construction machinery painting or steel structure buildings. However, the curing and cross-linking process of water-based epoxy coatings is centered on the curing agent, which gradually diffuses into the epoxy resin particles. The curing agent molecules first contact the surface of the epoxy resin dispersed phase particles and undergo a cross-linking curing reaction. As the reaction progresses, the relative molecular weight and glass transition temperature of the epoxy resin on the particle surface gradually increase, so that the diffusion rate of the curing agent molecules into the particles gradually slows down, which means that the curing reaction inside the epoxy resin dispersed phase particles Less than its surface, resulting in a low internal crosslink density, and ultimately not all epoxy groups have the opportunity to interact with the activating groups of the curing agent. Therefore, this paper studies different proportions of waterborne epoxy emulsion and curing agent. The results show that when m (epoxy emulsion): m (curing agent) = 7:3, the fire resistance and comprehensive performance of the coating are the best.
Abstract: The water-based epoxy fire retardant coating is formed by reaction curing, which not only has good anti-corrosion performance, but also has environmental protection and flame retardant performance, which is suitable for construction machinery painting or steel structure buildings. However, the curing and cross-linking process of water-based epoxy c...
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