Method for controlling double-screw reactor to produce TPU by reaction temperature rising and gel time

Abstract

The invention relates to a method which utilizes reactive temperature raising and gelation time to control a double-screw reactor to produce TPU. The method is characterized as follows: Molecular weight selected between 500 and 5000 in polyol; Chain extender including small-molecular diol and diamine; Isocyanate including aromatic series and aliphatic diisocyanate; Promoter; Screw parameter settings including control of material temperature, tempeature setting of material-feeding section of screws, temperature setting of reaction section and tempeature setting of material-discharging section;Rotational speed setting of screws; Rotational speed setting of a segmenting machine; Temperature setting of cooling water. The invention is particularly applied to the production of TPU in the relatively special formulation system, such as ultra-fast or ultra-slow reaction, ultra-high or ultra-low rigidity, non-crystallization (easy conglutination), etc.

Description

【Technical field】 [0001] The invention relates to a material temperature control method, in particular to a production method for controlling a reactor through reaction temperature rise and gel time. 【Background technique】 [0002] In 1958, Goodrich Company of the United States first launched commercialized TPU, and developed rapidly in developed countries in the following decades, mainly including Goodrich and Morton in the United States, Bayer and Basf in Germany, Merquinsa in Spain, and Townsend in Australia. Most of them are produced by the twin-screw body method, and the scale is that a single production line can reach an annual output of 1,000 tons. Our country started late, and most manufacturers still stay at the level of 100 tons / year batch method or even solution method. There are also domestic manufacturers who have purchased advanced twin-screw extrusion equipment from abroad, but due to lack of formula, process technology and supporting auxiliary equipment The ...

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Problems solved by technology

[0004] The invention discloses a method for controlling the production of TPU in a twin-screw reactor through reaction temperature rise and gel time. The main problems to be solved by the invention are: the setting of TPU production process parameters with different formulas; how to set the twin-screw reaction The process conditions and parameters of the extruder have always been a major problem in the production of TPU by this process method. They have been set based on experience for a long time, which is more difficult for the production of adhesive TPU with variable formulations; The reaction temperature rise and "gel time" are used to determine the activity of the reaction system and the speed of the reaction rate, and find out its correlation with the process parameters of the twin-screw reaction extruder to produce adhesive TPU. This method has been tested in the laboratory It is relatively easy and accurate to set the process parameters of the twin-screw reaction extruder (material temperature, feed ratio, temperature of each area of ​​the screw, speed of the cutting machine and water flow temperature, etc.) with a little experiment; the production technology is flexible and can produce many Adhesive TPU products with different reactivity and properties are especially suitable for the production of TPU with special formulas such as particularly fast or slow reaction, high or low hardness, and non-crystalline (easy to stick) TPU. It is at the leading level in China and has basically reached the advanced level of similar foreign technologies

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