Concentration Effect in Macrocyclic Polymer Synthesis

KeyWord : concentration ; Macro Chemistry ; Huang Jiaxian ; Chun Chunrong ; Zhang Min ; Li Fang ; Department of Chemistry ; Nankai University ; State Key Laboratory of Functional Polymer Materials for Adsorption and Separation. Tianjin, 300071 Specific conditions for competition based on ring formation and chain extension reactions. Under the guidance of the theory of high dilution, a highly dilute device designed to achieve infinite dilution and complete on-site looping was designed. The technical route for the synthesis of macrocyclic macromolecules was determined. And in the near critical concentration conditions to achieve quantitative, Introduction In the synthesis of polycondensed nylon 6 and Teri-lun, and other large industrial products, the most important means of synthesis is the use of bulk melt polycondensation method to obtain people's favorite can be used for clothing and film manufacturing product. However, it is well-known that even at the highest monomer concentration conditions, there is a competitive reaction to form linear humans and form cyclic human molecules, and there is always a lower proportion of oligomerization ring molecular polymerization degree in the product. Generally, it is 3 4. This fully shows that in the polycondensation reaction, the opportunity for the formation of linear macromolecules with the longest reaction to form the linear macromolecule is the most favorable for intermolecular collisions between molecules, and the opportunity for the formation of circular macromolecules is the highest during the formation of linear macromolecules. Due to the existence of competitive chain reactions, the formation of cyclic macromolecules requires more stringent concentrations of the system. 1 Under relatively low concentrations favoring the formation of loops, there will also be collisions between molecules to form linear patterns. The possibility of molecular, single-molecule collision and bi-molecular collision, respectively, forming ring macromolecules and linear macromolecules of the chain reaction of the ubiquitous plant bifunctional polycondensation on the selective reaction material concentration lower than the cyclization reaction Critical Concentration Not Incremental Human Bad Score Scores with High Conversion Semi-to-Quantitative Conversion 1 Test Section 1.1 Reagents Styrene 2 Vinylpyridine 2, Hydrogen Furaletin Naphthyl Naphthalene Cyclohexane, Bromine Bromide Toluene cyclizing agent linear hydrogenated furan alcohol 20001 liver 2000, measured molecular weight 196 butyryl chloride cyclizing agent, all reagents need to go through a rigorous treatment, to achieve seven water without oxygen and his impurities 7. Completely in accordance with the active yin From the requirements of 7 trial polymerization and cyclization reaction as well as polycondensation reaction, it needs to be stored under the conditions of protection from light, low temperature and ultra-high purity nitrogen. Styrene should be treated in addition to light, and it must be handled now. After the metal sodium is directly pressed, it is used to prepare naphthalene sodium initiator. After the 0.4 molecular sieve passes through 470, it is used for the cyclohexane solution of styrene 2 vinyl pyridine and cyclizing agent in an ultra-high purity nitrogen protective atmosphere. 2000 and protective drying of butyryl chloride in a hydrogen furan solution.

1.2 Test Instruments Gel Permeation Chromatography; determinations were made using 1 positive 7; 12, 8 gel permeation chromatographs. The intrinsic viscosity number 7 was measured using an Ubbelohde viscometer, and the weight average molecular weight Mw was measured using a Chromatix KMX6 type low-angle laser light scattering apparatus. The number average molecular weight Mn was measured using a 10 molecular weight measuring instrument from Company 3.

1.3 Synthesis of macrocyclic macromolecules 1.3.1 Synthesis of cyclic polyphenylene ethers by a multi-cycle method 8 Polymerization reaction system includes a 5,000, polymerization reactor, continuous reactor and 1 Torr, distillation system, initiator, and Sodium 1 sing Luo liquid. The cyclohexene hinge bromine pair of the steroid 8 is the benzene ring solution molecular sieve in which the feeding devices are all connected with the reactor and both are in ultra-high purity nitrogen gas protection condition. Prior to the active polymerization and ring-forming distillation distilling and feeding, as well as the reaction.

The entire system must be dried by high temperature baking. The total amount of monomer used to synthesize cyclo-polystyrene is 180 minutes. According to the design, the molecular weight is calculated based on the designed molecule. The 20,000 is cooled to 70% by 70% in the reactor. Add 301 to the meter. Naphthalene sodium solution. Hugh is a hustle and bustle. Styrene was added dropwise, and the color of the system was converted to red with a carbon negative 1. The jerseys dropped the ring 1 solution concentration of the ringing agent 1 into the system until the red color just disappeared. This is the first active anionic polymerization of 28 styrene in 1808 and the formation of a double-ended anionic polystyrene ring reaction. Continue to repeat the above steps to complete the multi-step cycle synthesis of macrocyclic polystyrene. The final product was obtained by concentrating and precipitating in precipitant methanol to dry to constant weight.

1.3.2 Continuing Looping Method Viewing Field Techniques Synthetic Cyclic Poly-2-Vinyl Pyridine 1 Lamps Will Have 13.151 Chiu can Initiate 1802 Naphthalene Sodium for Living Anionic Polymerization In the above system, secondary active anionic polymerization can satisfy the synthesis of poly-2 Vinyl batch steep double anion macromolecules are designed to have a molecular weight of 70,000, but the capacity of the polymerization reactor is changed to that of diethyltin 1 . Seventh, the bottom of the reactor is connected with a (1) ring-forming reactor connected with a ringing agent adding device and a stirrer.

The amount of butadiene 1 in the loop reactor is 250, and the whole system of anhydrous anaerobic and other protective measures 1 is a linear solution of a linear polyvinyl acetate pyridium dithiocyanate solution and a ring-forming agent under stirring conditions. The solution was added dropwise to the ring reactor under stirring. The color of the control system is slightly fluorescent and slightly reddish. The continuous loop reaction was completed and the reaction was completed after the completion of the addition. This reaction has no special requirements on the temperature, and there is no special requirement on the feed rate, but the synchronization of the feed must be controlled as required. The final product is obtained under the same conditions as above.

13.3 High-diluted field-of-view technique Synthesis of macrocyclic poly groups called hydrogenfuran, 1 method of this method does not advocate the characteristics of the two trays is a high dilution device connected between the loop reactor and the material of the cranial loop material feeder. , which is an online polyhydrofuranone alcohol sodium salt 15, dissolved in one volume, plus equivalent sodium naphthalene to form sodium salt, the specific operation from the slightly and ring-forming agent D. Acylhydrazone, Puwei Rao, and Magic 1 Solution 20 were slowly divided into two dilute side symbols in a highly dilute chamber prior to the ring formation reaction. Then it overflows into the loop reactor in a continuous + broken manner, and the loop reaction occurs. The solvent for the loop reaction is. Heating with agitation allows the material added in the loop reactor to be highly diluted. At the bottom of the two dilution side tubes there is a raw channel connection connected with the dilution of the upwardly inclined tube 5 . It can control the continuous overflow speed of the liquid in the inclined pipe according to the flow speed, overflow in this way to the existing 70,1, loop reactor, according to the differential design and manufacture of the dilution device, the material into The concentration in the loop reactor is a few 17 to nearly infinite extent. Conducive to the intramolecular reaction to form a ring-shaped score. And then the efficiency of the island to ring. The total time for the ring forming reaction is 18. The sodium salt and the ring-forming agent are added to the two side tubes of the high dilution apparatus at a uniform molar ratio. The excess of 5, the ring-forming agent may be added in a minor amount. And stop the reaction. High-dilution device's structure cabinet 1.

1 side tube 81 Xin Nankai University Journal Natural Science Edition 2 Results and Discussion 2.1 Synthetic product, shape, pain, guilty of swollen carbuncle, 裉 according to 0, milk 寤 懦, 懦 懦 牖 牖, 懋 懋. It is a reflection of the size of macromolecules. The hydrodynamic volume of the linear polymer is larger than that of the same structural unit and the hydrodynamic volume of the ring-shaped polymer with the same molecular weight 81. So the ring-shaped polymer, the spectrum of the wave lagging corpse type; the molecular matrix of the crest 2 by design The molecular weight of 20000 macrocyclic polyethylene vinyl Court 2 can. The crude product of the ring-shaped polystyrene synthesized by the multi-step recycling method has a bimodal property. The former peak is the peak of the linear parent peak of the ring-shaped polymer and the peak after the peak of 1=63 is identified as a ring-shaped polymer. According to sentence 23. Deduction plus effect. The macrocyclic poly(styrene)synthesized from the human-analysis-received-step-cycling method and the continuous ring-forming method using in-situ technology have been converted into macrocyclic poly-2-vinylpyridines with conversion rates of 50 and 70, respectively. For coarse samples. In their graded fractions, they were determined as single peak 10 and viscosity. The 17th and 17th boundaries of the last three fractions of macrocyclic macromolecules were identified.

The fractions of the linear precursors of the 0-line matrix of the parent matrix were 0 and 47, respectively, based on the fractions of the crude product of each of the 3 stepped samples identified as the cyclo-polystyrene and the cyclo-poly-2-vinylpyridine, which were close to each other. 50 and 70.

Due to the low molecular weight of the crude product and the three fractionated samples, the ring-shaped polyhydrofuran synthesized by the high-dilution in-situ technique is not suitable for distinguishing the viscosity difference, and the weight average molecular weight can not be determined. There are technically insurmountable difficulties in confirming the ring-shaped polymers, but the 0-spectrum of the city peak and 1 and 1 bands are absent, 0 and the closed proton characteristic peak butyryl chloride ring-forming agent or benzene ring proton features The appearance of peaks and the disappearance of the characteristic proton peaks of the radicals 4 and 4, the ring formation agent is brominated and the toluene ring formation agent is butyryl chloride 2.2 Concentration effects on the macrocyclic macromolecular synthesis. [1] The conversion rate of step-cycling method for synthesis of human ring polymer is not high, the concentration of the medium in the step method is relatively high, and the system is relatively large. This is mainly to obtain a sufficient amount of products as a last resort and the conversion rate of the macrocyclic ring is only 30. ; Multi-step cycle method can increase the conversion rate, but only 50.

The theory of ring chain equilibrium exists in the system. It was determined that the criticality of the ring chain equilibrium reaction is 4 for the ring-strengthening system and the critical concentration of the ring-chain equilibrium reaction, that is, the boundary point of the ring-forming reaction and the chain-extension reaction. Only when the concentration is lower than 7. aims. The 8 constant called in the formula can be said to be an astronomical number. It is absolutely impossible to reach the equilibrium on the right side of the formula 1 by using the simple dilution means of the equilibrium of the chain. this. The technological route for the synthesis of fire ring polymer by the step method is not a multi-step recycling method although it has been changed to Hong Kong.物料 Concentration of material in the continuous ring formation method can be 2-3 orders of magnitude lower than the concentration of the former, and the conversion into the ring is significantly improved. However, it is not possible to solve the basic question.

Synthetic macrocyclic macromolecules are the most ideal route for the synthesis of synthetic technology. Dilution parts that meet the requirements of relation 1 should be fulfilled. In the medium and small ones, the materials must be consumed instantaneously in the field. If the small loop concentration controls only one macromolecule in the reactor, it will only happen. It is obvious that the in-molecule reaction is a good solution to the high dilution field technology stress adopted in this paper. This can satisfy both the theoretical and practical requirements.

ring. The phase of the juice is added to the 1.9.101 linear poly furazan per second and is taken approximately 51 times, at a flow rate of 30 mt 1 . Divide this dilute solution, divided into 1 parts without considering the constants in formula 1 and other parameters within 18 days, the feed solution overflows into the loop reactor at any time, and the spilled liquid will remain in the main pipeline of the high dilution apparatus. Diluted by the solvent so that continuous dilution and flooding can meet the near-infinite dilution requirements of this synthetic bar. So far. The difficult process of practical operation is easily solved. From the theoretical analysis, such conditions can be seen as superior and required conditions.

A little lagging and slightly wider unimodality is sufficient to indicate that the macrocyclic conversion rate almost reached the goal of quantitative conversion. The diethyl ether solution of the crude product 1 was fractionated with a petroleum ether having a boiling range of 900, the first fraction of the three fractions obtained was 23, the number average molecular weight was 7400, and the first fraction accounted for 31 number average molecular weights. 3780; Grade 38, Number average molecular weight 2060; Loss 8. However, all graded samples and samples, in which no ridges were found. Less by rating. In the first and second fractions, a precipitate of a ring-shaped polymer having an integral multiple of the molecular weight of the parent may be mixed. Therefore, it is understandable that the value of the integral polyhydrofuran 2000 molecular weight is slightly lower in the measurement of the number average molecular weight.

The ring-forming reaction of extremely strong double-carbon anion macromolecules, which are easily deactivated by impurities, is technically more difficult to operate but controls the entire operating process. It is entirely feasible to use the high-dilution device described here. It is expected that this high dilution device will have an advantage over macrocyclic polymer synthesis in the synthesis of small ring molecules in pharmaceutical organic chemistry.

6 Huang Jiaxian, Li Chunrong. Determination of Cyclic Polystyrene Molecules by Chemical Method and Ultracentrifugal Sedimentation. Chemical Journal of Chinese Universities, 198568790 8 Huang Jiaxian, Chen Guohua, Li Chunrong et al. The gel permeation behavior of cyclic polystyrene and the calculation of the relative content of the midline formation of the cyclic polymer 1. Higher education school Huang Jiaxian, Li Chunrong. The theoretical derivation of the ring-shaped twisted-loop and ring-line of the ring-shaped polymer chain in a good solvent. Chemical Journal of Chinese Universities, 19856552556 15 Li Chunrong, Huang Jiaxian, Tang Xinyu. The synthesis and sign of cyclohydrofuran oligomers. Polymer Materials Science and Engineering, 1999, 1542629, continued on page 17. 1987 D. Wormert 8. Translated by Huang Jiaxian. Polymer chemistry base elbow. Beijing Chemical Industry Publishing. 1986 should be Sheng Kang, Yu Feng years. The principle of copolymerization elbow. Beijing Chemical Industry Press, 1984

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