brief history
19 16 Brooks' patent for rosin hydrogenation was first published in the United States. 1938, industrialized production of hydrogenated rosin by Hercules company. 1962, the Soviet Union began to produce hydrogenated rosin in Voronez petroleum complex. 1979, China built a pilot plant of hydrogenated rosin continuous process, and then built a factory for production.
nature
Hydrogenated rosin has the characteristics of good oxidation resistance, high thermal stability, small brittleness and light color. According to the different raw materials of rosin, it can be divided into hydrogenated resin rosin, hydrogenated wood rosin and hydrogenated floating oil rosin. Hydrogenated rosin contains about 75% dihydroabietic acid, fully hydrogenated rosin contains 1 ~ 14% dihydroabietic acid and 66 ~ 80% tetrahydroabietic acid.
manufacturing method
Hydrogenation of rosin can be divided into batch process and continuous process. ① Intermittent hydrogenation method: melt rosin, put it in an autoclave, add catalyst, seal the autoclave, flush the autoclave with nitrogen respectively, expel the air in the autoclave, then charge hydrogen to make it reach the required pressure, keep it for 65438 05 minutes, and then heat it to 65438 080℃. Start the agitator, continue to raise the temperature to the required reaction temperature, and indicate the progress of hydrogenation reaction through the pressure drop in the kettle. When the pressure in the kettle no longer drops, the hydrogenation reaction ends. Exhaust gas, opening that kettle, and take out the catalyst to obtain hydrogenated rosin. The main technological conditions of this method are as follows: the catalyst is 5% palladium-carbon catalyst, the dosage of palladium is 0.0 1% (calculated by rosin), and the particle size of activated carbon is 60 ~ 80 meshes; The reaction temperature was 270℃, and the hydrogen inlet pressure (30℃) was 10 MPa. (2) continuous hydrogenation method: adding massive rosin into a rosin melting pot, and heating and melting with indirect steam to make the temperature reach 65438 050℃. The melted rosin passes through a filter to remove impurities, and then enters a storage tank. Start the high-pressure pump to make rosin flow to the mixer through the heating pipe. Hydrogen is compressed from the gas holder by a compressor, and the oil and gas possibly entrained in the gas is removed by a residual mist separator, heated by a heater and sent to a mixer, and then sequentially enters a palladium-carbon catalyst reactor containing 5% palladium and rosin. And then enter a separator for separation. The separate hydrogen was cooled to 50℃. The high boiling point residual liquid is removed by the residual liquid separator, and enters the circulating machine for recycling together with the fresh hydrogen supplemented by the compressor. Hydrogenated rosin enters the storage tank through the receiver and is discharged regularly. The main technological conditions of this method are: the maximum operating pressure is 20 MPa, the maximum operating temperature is 270℃, the gas-liquid ratio is 5000∶ 1 (the ratio of hydrogen volume to molten rosin volume in standard state), and the space velocity is 0.4 hours-1.
quality index
Color is not deeper than the first grade (rosin color grade), softening point (ring and ball method) is not less than 72, acid value is not less than 160, ethanol insoluble matter is not more than 0.03%, oxygen absorption is not more than 0.2%, abietic acid is not more than 2.0%, and dehydroabietic acid is not more than 10.0%. Determination of abietic acid and dehydroabietic acid by ultraviolet spectrophotometry.
use
Mainly used for: ① adhesive. Hydrogenated rosin and its esters, as tackifiers for pressure sensitive adhesives and hot melt adhesives, increase the strength, softness and adhesion of adhesives; A moisture-proof adhesive with good thermal stability was prepared. (2) pigments and inks. Make stable photosensitive coatings, surface coatings of metals, plastics and fruits, and anti-solvent, anti-chemical or anti-fouling coatings. Modified with fumaric acid, it can be used for quick-drying ink. It can also be used as enamel developer. (3) Making water-resistant and light-resistant bacteriostatic agents for paper and soap. ④ As the main component of flux. The prepared flux has good activity and low corrosion. In addition, hydrogenated rosin can be used as a food additive for beverages and chewing gum; Used as rubber additive, tooth adhesive, lens adhesive, etc. In the food hygiene laws of the United States, China and Japan, specially treated hydrogenated rosin esters are approved to be used in chewing gum and soft drinks, or as the main components in adhesives, coatings and food packaging paper.