Polysulphones preparation

A polysulphone prepared from bisphenol A and 4,4 -dichlorodiphenyl-sulphone... 

The polysulphonate prepared by condensation of diphenylether-4-4 -disulphonylchloride and 4,4 -dihydroxydiphenyl namely,... 

Polysulphone prepared from 2,2-bis(4-hydroxyphenyl)propane and 4,4-dichlorodiphenylsulphone is particularly stable to electron irradiation [381]. Retention of flexural strength and modulus are retained... 

Polysulphones are polymers which contain recurring sulphone groups (-SO2-) in the main chain. Aliphatic polysulphones, prepared by reaction of sulphur dioxide with olefins, have been known for many years but lack of thermal stability has precluded any commercial utilization. In 1958 the preparation of stable aromatic polysulphones was described [5] and since this time a large number of such polymers has been investigated. However, at the present time, the only aromatic polysulphone to have achieved commercial significance is that prepared from 2,2-bis(4 -hydroxyphenyl)propane (bisphenol A) and 4,4 -dichlorodiphenyl sulphone. Only this polysulphone, manufacture of which was started in 1965 by the Union Carbide Corp. (U.S.A.), is described in this chapter. 

A blow-moulded container, cylindrical in shape but with one spherical end, is prepared from the polysulphone whose creep curves at 20°C are illustrated in Figure 9.9. The cylindrical part of the container has an outside diameter of 200 mm and is required to withstand a constant internal pressure of 7 MPa at 20°C. It is estimated that the required service lifetime of the part will be one year and the maximum allowable strain is 2%. What will be the minimum wall thickness for satisfactory operation ... 

In principle there are two main routes to the preparation of polysulphones ... 

A consequence of the reaction is that it is possible to produce a range of polymers by reacting bisphenates with appropriately activated aromatic dihalides. In the case when the dihalide is activated by the presence of a sulphone —SO,— group the polymers may be referred to as polysulphones. The Amoco materials are prepared in this way. 

A range of polysulphones has been prepared with a variety of bis-phenols other than bis-phenol A. As might be expected from the discussion in Chapter 4 and from experience with the range of polycarbonates (Chapter 20), replacement of the isopropylidene link with a methylene, sulphide or oxygen link depresses the Tg whilst —C(CgH5)2— and sulphone links raise it. The bis-phenol derived from norcamphor leads to a polysulphone with a Tg of 250°C (195°C for a Udel-type polymer). 

The chemistry and technology of this class of polymer may be considered as an extension to those of the polysulphones, particularly insofar as there are strong parallels in preparative methods. The two polymer classes also have strong structural similarities with polysulphones containing the structure (I) and the polyetherketones the structure (II) of Figure 21.6. 

Method for Microwave Acid Digesting of Polyurethane, Polyphenylene Sulphite, Polysulphone and HDPE. Sample preparation for analysis of polyurethane, polypropylene terephthalate, polyphenylene sulphite, polysulphone, HDPE, PVC, polyethers, cellulose acetate, and natural wools for metal content is as for nylon with an additional step involving charring the sample prior to digestion. 

Fig. 3 shows ceramic fibers prepared by the polysulphone process varied between 100 pm. .. 1000 pm. 

Modified silicon-containing polycarbonates have been prepared in solution and their transition temperatures assessed. Block copolymers of bisphenol-A-polycarbonate-bisphenol-A-polysulphone and acrylates and methacrylates grafted onto polycarbonate film have also been prepared and evaluated, as have mixed polycarbonate systems based on 2,2 -bis(4-hydroxyphenyl)propane, 2,2 -bis(4-hydroxy-3,5-dibromophenyI)propaneandtetrabromophenophthalein. Molecular relaxations in aliphatic polycarbonates have been studied by the method of thermally-stimulated currents and the thermal ageing of polycarbonates based on polycyclic diphenols has been assessed by studies of mechanical properties. 

Rubber mixes were prepared with a David Bridge (UK) roller mixer. Specimen for further examinations were vulcanized in a steel mold at 160 °C, during time determined rheometrically with a WG 05 instrument (Metalchem, Poland), according to ISO 3417. Liquid polysulfide rubber was cured at room temperature by means of chemical initiator, activated by Mn02. Polysulphone specimen were prepared by cutting off from a rod. 

But, the greatest growth of BPA production started at the beginnings of the Age of Plastic in the 1950s. At that time, industrial fabrication of polycarbonates and epoxy resins started [12], and Bisphenol-A became the primary monomer for their synthesis. As a difunctional monomer, later on BPA became one of the most important raw material used for synthesis of other polymers as well as polymer additives. Now, BPA is also used in the production of polyesters, polysulphones and polyether ketones. Its use for formulation and preparation of polymer additives (e.g., antioxidants, plasticizers, polymerization inhibitors and halogenated flame retardants) is still its another important application. 

Udel polysulphone was the first polysulphone to be introduced commercially by Union Carbide in 1965. It is prepared by the reaction of the disodium salt of bisphenol A with dichloro-diphenylsulphone... 

Photolysis of polysulphone 4.84) prepared from the polycondensation of bisphenols (e.g. 2,2-bis-(4-hydroxyphenyl)propane) with 4,4 -dichlorodiphenyl-sulphone occurs by the following mechanism [4, 79, 740] ... 

There are two principal methods for the large scale preparation of aromatic polysulphones, i.e. polyetherification and polysulphonylation. 

Polyaryletherketones may be prepared by methods which are analogous to those used for polysulphones, namely polyetherification and polyacylation. 

A difficulty in the preparation of polyaryletherketones is that the polymers readily crystallize (unlike the polysulphones) and thus precipitate from most organic solvents as they are being formed giving a low molecular weight... 

---