EP-4206258-B1 - A METHOD FOR SYNTHESIS OF POLYKETONE IN HIGH CONVERSION RATE BY USING LOW AMOUNT OF CATALYST

Inventors

• EZDESIR, AYHAN
• KARACA, Sila
• ALPARSLAN, Alp
• BATI, Bige
• OZTURK, TURAN
• EROGLU, Mehmet S.
• ISCI, Recep
• KARAKAYA, Ozan

Dates

Publication Date

20260506

Application Date

20211230

Claims (2)

1. A method for high conversion polyketone synthesis with the use of minimum catalyst, comprising the process steps of: I. adding palladium (II) sulfate (PdSO 4 ), 1,3-bis(diphenylphosphino)propane (Dppp) ligand and methanol/methyl ethyl ketone (MeOH/MEK) solvent system in the range of 90/10-10/90 (V/V) by volume to the reactor, II. synthesis of polyketone by feeding carbon monoxide and ethylene reactives (1-5/25-30) (mol/mol) to the system at a total pressure of 25-35 bar and performing the polymerization by adjusting the reactor temperature to 60-80°C for 4-10 hours, III. discharging the remaining gas in the system and removing the suspended solution from the reactor, IV. Filtering the obtained polyketone and washing it with methanol/methyl ethyl ketone (MeOH/MEK) solvent system in the range of 90/10-10/90 (V/V) by volume, V. drying the filtered polyketone in an oven under vacuum.
2. A method according to claim 1, wherein said methanol/methyl ethyl ketone (MeOH/MEK) solvent system in the process step I comprises 25% MEK and 75% MeOH by volume.

Description

Technical field of the Invention The invention relates to a method for the synthesis of polyketone which is an ethylene-carbon monoxide thermoplastic copolymer in high conversion rate by using low amount of catalyst by means of using solvent system in specific rates formed by methyl ethyl ketone (MEK) and methanol (MeOH) mixture. State of the Art Polyketones in the aromatic polyether class are a family of high-performance thermoplastic polymers. Polyketones are widely used in almost all areas of the industry, including the aircraft and automotive industries, since they have outstanding strength properties, resistance to heat and chemicals, high memory, gas barrier properties, tendency to resist solvents and high abrasion resistance. Considering the amount of energy required to sustain processes that require large energy expenditures such as polyketone synthesis, the energy loss caused by polyketone synthesis brings along economic and environmental problems. Considering that all reactions to be carried out in order to minimize energy use must be carried out at ambient conditions, that is, at room temperature and atmospheric pressure, the energy losses and global, economic, and environmental damages caused by polyketone syntheses, which include applications requiring high temperature and high pressure, are an undeniable fact. Palladium (Pd) catalyst is the most common catalyst used in polyketone synthesis. Although catalysts increase the rate of a chemical reaction, the damage caused by the use of Pd catalysts to the environment is an inevitable fact. For this reason, it is of great importance to carry out studies to minimize the use of non-environmentally friendly catalysts when producing new chemicals. In addition to the use of low-rate catalysts, obtaining polyketone with high conversions from low-rate catalysts is of great importance when considered in terms of today's energy consumption problem. In polyketone syntheses in the state of the art, the resistance of the synthesized polyketones, particularly to heat, is very low due to the use of solvents in wrong forms and ratios. Considering that polyketones are used in almost every field of industry, it is of great importance that they show high resistance to heat. In a study conducted by S. Chen et al. in the state of the art, polyketone synthesis was carried out with the use of cationic diphosphazene monoxide-palladium complexes in order to increase the processability of polyketone. In this reaction, 0.356 g of polyketone was obtained by using 10 micromoles of Pd catalyst (palladium diphosphazene monoxide) at 110 °C and under 40 bar pressure. As for the solvent, only toluene was used. In this study, although the functionality of polyketone was tried to be increased, it was not successful enough. In addition, it is very difficult to say that a high rate of polymer conversion was achieved with the use of low amount of catalyst in the said study.[1] In the state of the art, there are no studies aimed at minimizing the use of Pd catalyst in polyketone syntheses. In addition, it is not possible to come across any studies on the synthesis of polyketone at the maximum rate with the use of minimum Pd catalyst in the state of the art. In addition to all these, considering the amount of energy required to maintain processes that require large energy expenditures such as polyketone synthesis, it is also not possible to come across any work in the state of the art to reduce the temperature and pressure parameters in order to minimize the energy use in polyketone synthesis realised in the contemporary techniques. Also, in the studies conducted on polyketone syntheses, it cannot be mentioned that there is a study specific to the solvent used in order to increase the efficiency and product quality in the said polyketone syntheses. In the prior art, C. E. Ash has studied about alternating olefin/carbon monoxide polymers as a new family of thermoplastics. CARILON® polymers are semicrystalline thermoplastics derived from simple and abundant raw materials of carbon monoxide and ethylene (or other a-olefins.) These new materials have resulted, in part, from a high activity catalyst invention which enables the polymer to be produced with perfectly alternating units of CO and olefin [2]. The patent application no. US4894435A is related to a of producing linear alternating polymers of carbon monoxide and at least one ethylenically unsaturated hydrocarbon in the presence of novel catalyst composition prepared from a palladium compound, a non-transition metal salt of a non-hydrohalogenic acid having a pKa less than 6, bidentate phosphorus ligand and a ketone or ester carboxylic compound. Preferred hydrocarbons are hydrocarbons of 2 to 20 carbon atoms inclusive, more preferably 2 to 10 carbon atoms inclusive. The palladium compound employed in the novel catalyst composition of the invention is a palladium salt of an organic acid, preferably a carboxylic acid of up to about 10 carb