Synthesis Of Producting Process Of Propylene₁-butene's Random Copolymer

Polypropylene has a wide range of applications in all aspects of life,but isotactic polypropylene has defects of high hardness and poor transparency.At present,atactic polypropylene is prepared by the polymerization of ethylene and propylene to improve the performance of the product,but the material has a tendency to become soft and the tensile modulus is decreased.In order to improve the performance of the product and gain more economic benefit,1-butene will be used as a co-monomer to produce atactic polypropylene and the products will be marketed,because 1-butene is much cheaper and readily available.In this thesis,theoretical analysis shows that the performance of atactic polymer based on propylene and 1-butene is better than that of atactic copolymer of ethylene propylene.At the same time,atactic polymer of propylene and 1-butene is produced by the second generation loop-tube method,the performance of atactic propylene and 1-butene co-polymer is better than that of atactic ethylene and propylene copolymer as suggested by parameter comparison and actual usage.In conclusion,this study proves that the theoretical analysis is correct.The thesis mainly involves the following seven aspects:(1)The modification of propylene copolymer process and the adjustment of catalyst,additives,hydrogen,propylene and butene on the DCS system are carried out to obtain the optimum parameters for actual control;(2)Analysis of the production process parameters of propylene butene copolymer flash evaporation system;(3)Study of the influence of different butene content on reaction process;(4)Comparison and analysis of parameters of propylene copolymer and ethylene propylene copolymer;(5)Effect of reaction temperature on the content of butene in polymer;(6)Analysis of the effect of copolymerization monomer content on the content of soluble polymer xylene;(7)Cost-profit analysis.Research results show that:(1)According to the olefin polymerization heat of fusion data,adding a separate butene system to each set of production equipment,without increasing the heat removal capacity,we can produce propylene butyl copolymer products.Modification of the process based on the above fact,in the actual production test,we can produce high quality propane copolymers,and obtain the stable parameters of the production of PPRMT.It shows that the scheme of the process transformation is feasible;(2)If propylene contains 1-butene,heat of vaporization is increased,and the heat of vaporization increases in magnitude with the increase of butene-1 content.Therefore,for the distillation of propylene containing 1-butene,there should be certain amount of excess heat load.The temperature of the flash evaporation system needs to increase 3 degrees over the homopolymer;(3)When butene content is greater than 6%,not only the product has quality problems,but also the sticky material will lead to blockage of the entire reaction system;(4)The propylene butyl copolymer PPRMT has similar functions with ethylene propylene copolymer HTNX,and the transparency of PPRMT is superior to that of HTNX,and the content of PPRMT cold xylene is lower than that of HTNX.PPRMT is more suitable for applications in food and medical materials.When atactic polypropylene is used in medical and food industry,1-butene is more suitable as co-monomer;the tensile strength,Izod impact strength and flexural modulus of PPRMT are higher than that of HTNX,the overall PPRMT mechanical properties are better than those of HTNX;(5)In the case when the concentration of 1-butene is less than 11%,the content of 1-butene in the polymer at each reaction temperature doesn't vary much,which indicates that the reaction temperature has little influence on the content of 1-butene.When the feed monomer concentration of 1-butene was greater than 11%,with the decrease of reaction temperature,the content of 1-butene in the polymer tends to rise,meaning that the reaction temperature is negatively correlated with the content of 1-butene in the product.Under the same feed ratio,the higher the temperature,the lower the 1-butene's content of the product,and vice versa.It indicates that the polymerization rate of butene-1 decreases with the increase of temperature;(6)In the case of the same copolymer molar content,the content of cold xylene soluble at room temperature of the random copolymer of c and d was reduced by about 50% compared with that of the random copolymer of c and b,which indicated that the random copolymer of c and d was more suitable for transparent or heat sealing materials.The content parameters of cold xylene soluble substance in products were compared,indicating that the PPRMT of propylene / 1-butylene products is more beneficial to the application in food and medical materials;(7)The price of PPRMT and HTNX products is 11,000 yuan/ton,the production cost of polymerized ethylene is about 9000 yuan/ton,the production cost of polymerized butylene is about 7000 yuan/ton,the cost of propylene / 1-butylene is cheaper and the profit is more objective.