Terpolymers compositional analysis

Compositional Analysis of a Terpolymer Photoresist by Raman Spectroscopy... 

Since the late 1960 s a few papers have demonstrated compositional analysis of various polymer systans by Raman spectroscopy. For example, Boerio and Yuann (U) developed a method of analysis for copolymers of glycidyl methacrylate with methyl methacrylate and styrene. Sloane and Bramston-Cook (5) analyzed the terpolymer system poly(methyl methacrylate-co-butadiene-co-styrene). The composition of copolymers of styrene-ethylene dimethacrylate and styrene-divinylbenzene was determined by Stokr et (6). Finally, Water (7) demonstrated that Raman spectroscopy could determine the amount of residual monomer in poly(methyl methacrylate) to the % level. This was subsequently lowered to less than 0.1% (8). In spite of its many advantages, the potential of Raman spectroscopy for the analysis of polymer systems has never been fully exploited. 

In the pmr data for the terpolymer, overlap between the CH3 absorption of the oxime ester and the backbone absorption is greater than in the copolymer pointed out in Figure k. Thus, while the agreement between the Raman and pmr data for the terpolymer is not very good, (lT-32 difference), it is completely within the experimental error of the pmr data. This large error and the fact that pmr can only distinguish two of the components of the terpolymer demonstrate that it is unsuited for compositional analysis of this system. Based on the agreement with published reactivity ratios and with the elemental analysis of the P(M-CN) copolymer, it is assumed that the Raman data are more accurate. 

The terpolymerization of CPT-SO2 and acrylonitrile is shown in Table II. It was necessary to accelerate the polymerization by adding azobisisobutyronitrile (AIBN) as initiator. The nature of the propagating species may not be different with a different initiator. Polymerization ceased at a low conversion at 40 °C in toluene. The terpolymer composition calculated from elemental analysis of C, H, N, and S showed an equimolar ratio of CPT and S02. The terpolymers are white powders, soluble in DMF, can be cast into transparent film different from the CPT-SO2 copolymer, and showed melting temperature without decompo-... 

Terpolymer composition by analysis for N2 and Br2 (styrene and butadiene by difference). 

The applicability of this model for the calculation of the composition of terpolymers produced at low conversions was demonstrated for a number of three component systems (see, for example, [6, 132]). This statement follows from the good agreement of the values of the terpolymer composition determined experimentally with those calculated according to the Alfrey-Goldfinger equations [45] within the framework of the terminal model. All six parameters of this model are considered to be known from the preliminary analysis of the data on three binary systems selected from the given three monomers. 

This conclurion is stron y suppc rted by the compositional analysis of the network resulting from sulfur curing of two different terpolymers. In fact, the data obtained (Table 17) in the case of (V)-EPTM show ... 

Finally, Section 5 is concerned with methods for composition analysis in C2-C3-diene terpolymers. 

Terpolymer compositions were determined using elemental analysis for carbon, nitrogen, and sulfur. 

In an extension of the above studies, terpolymers of 3, 4, and 5 (series II) (Scheme 5) were synthesized (57). Compositional analysis for this series of terpolymers is listed in Table 2. Weight-average molecular weights for this series range from 3.0 x 10 to 7.9 x 10 g mol It was initially postulated that these polymers would exhibit polyzwitterionic or polyelectrolyte behavior depending upon the pH. However, at low pH values, hydrogen bonding between the carboxylic acid and amide moieties limits solubility even in the presence of salts. Therefore, all solution studies were conducted at pH = 8. Under these conditions,... 

Kranz and co-workers [126] have shown that acrylonitrile can he determined in styrene - butadiene - acrylonitrile terpolymers via a determination of organic nitrogen by the Kjeldahl procedure. Styrene units can be can be determined by infrared spectroscopy. Butadiene units can be determined by the iodine monochloride procedure. The compositional analysis and details of the microstructure of butadiene - acrylonitrile copolymers can be obtained by Raman spectroscopy [127]. 

Such a distinction in composition inhomogeneity of the copolymers may have caused the variation in transparency which was observed experimentally by Sloco-mbe [36]. He examined forty-four three-component systems and established several empirical rules enabling the interpretation of experimental data on the transparency of high-conversion terpolymers. These empirical rules were explained later [37] in terms of the theory of dynamic systems whose methods have been successfully employed for qualitative analysis of the solutions of the set of dynamic... 

It is worth emphasizing in conclusion of this section that a similar analysis of the dynamic system (8.3), (8.4) could be also carried out for terpolymerization, since by now experimental data are available on the dependence of the copolymerization rate on monomer feed composition for terpolymers of methyl methacrylate and styrene with either diethyl maleate [344], N-vinylpyrrolidone [344], or acrylonitrile [346]. 

Pentachlorophenyl acrylate, (1), was terpolymerized with methyl methacrylate (MMA) and n-butyl acrylate (nBA) (Scheme III) to give a latex containing 537 solids and a pll of 4.7 which was adjusted to 6.8 by adding aqueous NaOH. The latex was stable up to pH =10. A small aliquot vzas coagulated and the resulting polymer purified. Its intrinsic viscosity was 3.1 /g and analysis indicated 2 mole percent (1), 587 CIA and 40" nBA. Similar terpolyner latices were prepared from acrylates (2) and (3) (Scheme III). Another terpolymer latex made from (3), vinyl acetate, and 2-ethylhexyl acrylate contained 547 solids. Tliese latices and their compositions are summarized in the Table 1 and a sample experimental procedure is given in the experimental section. 

Polymerization. Terpolymers of PMVE and TFE with either of the monomers containing a phenoxy group have been prepared in a pressure vessel using an aqueous redox polymerization system. The compositional molar TFE/PMVE ratio in the preferred polymer is about 60/40. The third monomer polymerizes at about the same rate as the PMVE and is fed either neat (as a liquid) or in Freon F-113 solution. Infrared analysis of the band at 10.0/a indicates 75-85% incorporation of the phenoxy compound over the 1-4 mole % monomer change range. One to 2 mole % of the crosslink monomer must be incorporated in the elastomer to ensure good vulcanizate properties. 

The versatility of Raman spectroscopy for the on-line analysis of polymers both in the laboratory and also in-situ on the production line is demonstrated and the benefits and disadvantages of the technique as an on-line method are considered. Application of the technique to an analysis of acrylic terpolymers, monitoring of polymerisation and on-line measurement of morphology/composition is... 

A modified internal standard method has been developed to determine the compositions of terpolymers of maleic anhydride with styrene and a methacrylate or an acrylate. The method involves IR spectrophotometry of the samples. IR spectra are recorded by means of the potassium bromide technique. The IR analysis is based on integrated absorption of the anhydride and ester carbonyl groups. 9 refs. 

All polymers were analyzed by NMR, FT-IR, and UV-VIS spectroscopy as well as by thermal analysis (TGA) (10,11). The composition of the used co- and terpolymers was determined by H-NMR and it was varied between 20-50 % photo active monomer, 0-50% anchor monomer and 50-80 % MMA depending on the final purpose. The imaged films shown in this manuscript had the... 

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