Dichlorodiphenylsulfone

Nucleophilic Substitution Route. Commercial synthesis of poly(arylethersulfone)s is accompHshed almost exclusively via the nucleophilic substitution polycondensation route. This synthesis route, discovered at Union Carbide in the early 1960s (3,4), involves reaction of the bisphenol of choice with 4,4 -dichlorodiphenylsulfone in a dipolar aprotic solvent in the presence of an alkaUbase. Examples of dipolar aprotic solvents include A/-methyl-2-pyrrohdinone (NMP), dimethyl acetamide (DMAc), sulfolane, and dimethyl sulfoxide (DMSO). Examples of suitable bases are sodium hydroxide, potassium hydroxide, and potassium carbonate. In the case of polysulfone (PSE) synthesis, the reaction is a two-step process in which the dialkah metal salt of bisphenol A (1) is first formed in situ from bisphenol A [80-05-7] by reaction with the base (eg, two molar equivalents of NaOH),... 

A mixture of dimethyl sulfate with SO is probably dimethyl pyrosulfate [10506-59-9] CH2OSO2OSO2OCH2, and, with chlorobenzene, it yields the 4,4 -dichlorodiphenylsulfone (153). Trivalent rare earths can be separated by a slow release of acid into a solution of rare earth chelated with an ethylenediaminetetraacetic acid agent and iodate anion. As dimethyl sulfate slowly hydrolyzes and pH decreases, each metal is released from the chelate in turn and precipitates as the iodate, resulting in improved separations (154). 

Other apphcations for monochlorobenzene include production of diphenyl-ether, ortho- and i ra-phenylphenol, 4,4 -dichlorodiphenylsulfone, which is a primary raw material for the manufacture of polysulfones, diphenyldichlorosilane, which is an intermediate for specialty siUcones, Grignard reagents, and in dinitrochlorobenzene and catalyst manufacture. 

High molecular weight polymers have been recently prepared by condensation of alkali metal salts of biphenols with activated halides such as 4.4 -dichlorodiphenyl sulfone 50). The polymer (II) prepared from 4.4 -isopropylidenediphenol and 4.4 -dichlorodiphenylsulfone is now commercially available. 

Typically, polysulfones are prepared by the reaction of disodium bisphenol A with 4,4 -dichlorodiphenylsulfone. 

The kinetics of polycondensation hy nucleophilic aromatic substitution in highly polar solvents and solvent mixtures to yield linear, high molecular weight aromatic polyethers were measured. The basic reaction studied was between a di-phenoxide salt and a dihaloaromatic compound. The role of steric and inductive effects was elucidated on the basis of the kinetics determined for model compounds. The polymerization rate of the dipotassium salt of various bis-phenols with 4,4 -dichlorodiphenylsulfone in methyl sulfoxide solvent follows second-order kinetics. The rate constant at the monomer stage was found to be greater than the rate constant at the dimer and subsequent polymerization stages. 

If the reaction rate of the functional groups is independent of the size of the molecule to which it is attached, the rate constant, k, should be truly constant during the polymerization. Thus, a plot of 1/C vs. t should be linear with a slope equal to k. To test these ideas, the reaction rate of 4,4 -dichlorodiphenylsulfone with the potassium diphenoxide salts of three bisphenols was measured in dimethyl sulfoxide (DMSO) solvent. These bisphenols are shown below (I, II, and III). 

Reagents. Para-Bis-A polymerization-quality bisphenol-A (Dow Chemical Co.) was recrystallized once from toluene. Pfaltz and Bauer s 4,4 -dichlorodiphenylsulfone was recrystallized three times from ethanol. Reagent phenol (Baker) and 4,4 -biphenol (Eastman s white label) were used as received. Spectroquality methyl sulfoxide, dimethyl acetamide, and dimethylformamide (Matheson, Coleman, and Bell) were used as solvents. 3,5,3, 5 -Tetramethyldiphenoquinone and hexamethylphosphor-amide (Aldrich) were used as received. 

Figure 3. Polymerization of 3,5,3 , 5 -tetrameihyl-4,4 -biphenol with 4,4 -dichlorodiphenylsulfone...

In this theoretical analysis we have assumed an equal reactivity of both functional groups on 4,4 -dichlorodiphenylsulfone (see section on reaction rate of potassium phenoxide for a discussion of this assumption). This reaction sequence can be treated kinetically in the following... 

Table I. Reaction Rate Constants for Bisphenols Which React with 4,4 -Dichlorodiphenylsulfone in DMSO...

Figure 4. Reaction rate (k2) vs. temperature for bisphenol A-4,4 -dichlorodiphenylsulfone polymerization...

Reaction Rate of Potassium Phenoxide. As a test of the kinetics theory presented, the potassium salt of phenol was allowed to react with (1) p-chloronitrobenzene and (2) 4,4 -dichlorodiphenylsulfone. 

In the second case, the phenoxide is monofunctional, but the chloro-monomer is difunctional. This reaction provided a test of the relative reactivities of the two chlorines on 4,4 -dichlorodiphenylsulfone. Figure 5 does show a slight curvature which indicates a difference in the reactivities. Using Equations 8 and 9, the reaction rate constants (fci and k2) were determined to be 0.10 and 0.053 liter/mole-min. Therefore, the assumption of equal chlorine reactivity (which was made in deriving these equations for the polymerization reaction) is not entirely correct. A complete theoretical analysis would be very involved at least two more reaction rate constants would be necessary, and the experimental data obtained would not be sufficient to determine all of these constants. 

Effect of Solvent. Besides polymerizing in DMSO solvent, we also polymerized bisphenol A with 4,4 -dichlorodiphenylsulfone in the following solvents (a) mixtures of DMSO and chlorobenzene (b) di-methylacetamide (DMAc) (c) dimethylformamide (DMF) (d) hexa-methylphosphoramide. We found that the reaction rate constant (k2) was the same in the chlorobenzene-DMSO mixtures as in pure DMSO. However, if the chlorobenzene concentration was too high, the solubility of the bisphenol-A-diphenoxide salt was reduced, thereby precipitating some of the salt and effecting a slower polymerization. At a monomer concentration of 0.075M, the critical chlorobenzene concentration for precipitation was found to be between 35 and 50 vol. % at 100 °C. 

Other poly(sulfones) can be obtained similarly to poly(sulfides) by polycondensation. Many of these sulfones also contain an ether group in the backbone. A typical reaction for the formation of a poly(ether sulfone) is that of 4,4 -dichlorodiphenylsulfone with 4,4 -sulfonyldiphenol or bisphenol S in the presence of K2CO3 (as a base) as shown below ... 

The class of poly(ether sulfones) includes a number of compounds obtained by polycondensations similar to that between bisphenol A and 4,4 -dichlorodiphenylsulfone, which generates PES. Among more common poly(ether sulfones) are poly[oxy(1, T-biphenyl)-4,4 -diyloxy-1,4-phenylene-sulfonyl-1,4-phenylene] (PPSF) CAS 25608-64-4, which is synthesized from the reaction of 4,4 -dichlorodiphenyl-sulfone with 1, T-biphenyl-4,4 diol in the presence of a base, and poly[oxy-1,4-phenylenesulfonyl-1,4-phenyleneoxy-1,4-phenylene(1-methylethylidene)-1,4-phenylene] (PSF) CAS 25135-51-7, which is obtained from bisphenol A and 4,4 -dichlorodiphenylsulfone. 

In principle, cyclic systems with six units cannot be formed directly in this reaction, however, in a related reaction in which the oxidized form of 8. that is 4,4 -sufonylbis(benzene thiol) is reacted with 4,4 -dichlorodiphenylsulfone, the cyclic system containing six aromatic rings has been found to predominate. This arises by intramolecular displacement of a bridging thioether group rather than a terminal halide. 

At VirginiaTech, 3,3 -disulfonate, 4,4 -dichlorodiphenylsulfone co-monomers with varying degrees of sulfonation were prepared from commercially available monomers. Nuclear magnetic resonance (NMR) spectroscopy was conducted on selected polymeric films to investigate the level of sulfonation. The NMR results showed that the sulfonation levels could be quantified very accurately. The water uptake of bi-phenol sulfone (BPSH) films increased with an increase in the degree of sulfonation. The membrane samples drawn from BPSH40 with 20, 30 and 40 K molecular... 

Polyetherification processes form the basis of commercial polysulfone production methods. For example, the Udel-type polymer (Union Carbide) is prepared by reacting, 4,4 -dichlorodiphenylsulfone with an alkali salt of bisphenol A. The polycondensation is conducted in highly polar solvents, such as dimethylsulfoxide or sulfolane. 

The data for high-temperature polycondensation of different disodium salts of the bisphenols with 4,4 -dichlorodiphenylsulfone (DCDPS) are used [47], The bisphenols denomination, their conventional signs and also the values of poly condensation rate constants k and En are adduced in Table 2. Besides, the kinetic curves conversion degree — reaction duration (Q -1) of polycondensation, adduced in the work [47], were used. 

Polysulfones are a family of engineering thermoplastics that exhibit excellent high-temperature properties. Many variations of this material have a continuous use temperature of 150 C and a maximum temperature of around 170 C. Polysulfones are produced by the Friedel-Crafts reaction of sulfonyl chloride groups with aromatic nuclei, or by reacting 4,4 -dichlorodiphenylsulfone with alkali salt of bisphenol A. The latter polycondensation is conducted in highly polar solvents, such as dimethylsulfoxide or sulfolane. These materials can be injection molded into complex shapes and can compete with many metals. The following is the chemical structure ... 

For instance, a chlorine-terminated fully aromatic sulfone, 4,4 -dichlorodiphenylsulfone (DCDPS) was reacted [84] with two aromatic diols, namely dihydroxy-diphenylsulfone (DHDPS) and hydroquinone (HQ). The reaction product was RLS80, a chlorine-ended copolyethersulfone with ESES units -( )-S02-( )-0-( )-S02-( )-0- and EES units -c )-S02-( )-0-( )-0-, where ( ) is a phenyl ( = Q ). Figure 45.22 contains the MALDI spectrum of RLS80 along with an expansion of the 3.65-4.44 kDa region. The spectrum shows more than 130 well-resolved peaks, ranging from 1.0 to 9.0 kDa. The most intense peaks are due to chains B and B, where... 

Test reaction was conducted for diphenylolpropane (DPHP) disodium salt and 4,4 dichlorodiphenylsulfone (DCHDPHS) in OS-D case, and phenylphtalein disodium salt (PHPH) and 4,4 - dichlordiphenylsulfone in OS-PH case. 

In case of getting oligoketons instead of 4,4 - dichlorodiphenylsulfone were used the corresponding molar quantity of 4,4 - dichlorbenzophenone (DCHDBPH). 

In 1990, Amoco Performance Products, Inc., introduced an even higher-performance sulfone polymer derived from the condensation polymerization of 4,4 -dichlorodiphenylsulfone with 4,4 -dihydroxy-diphenyl (also known as biphenol). This polymer, which came to be known as polyphenylsulfone (PPSF) and which was introduced commercially under the trade name Radel R, has the following repeat unit structure ... 

Table 2. Glass-Transition Temperatures of Polysulfones Produced from the Polycondensation of 4,4 -dichlorodiphenylsulfone with Various Bisphenols ...

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