CERTAIN CHARACTERISTICS OF GLASS-FIBER AND THE STRUCTURE OF GLASS A. F. Zak Direct methods of structural analysis have not yet enabled a clear conception of the structure of glass to be worked out. Many questions in connection with glass structure are still open to argument. In view of this great importance is attached to various physicochemical investigations which might throw light upon some in dividual aspects of this highly complex problem Ante. Among these investigations, the study of glass solubility under the effects of corrosive media is of definite interest. These investigations did not, however, produce the expected results. In the reaction of glass with difficult to obtain reliable data on those processes which do take place under these circumstances make it ous agents, the soluble constituents are not entirely eliminated from it, while secondary reaction To a certain extent, the acid treatment of sodium borosilicate glasses provides an exception. It is well known that when a number of glasses of this system are reacted with acid, the sodium borate constituent is al most completely driven off, leaving only the predominantly siliceous framework which contains nearly 96%0 SiOz A method of making products from quartzoid glass which possesses a number of valuable characteris ics, has been developed on this basis, Many years investigation of the structure and properties of sodium borosilicate glasses, both primary and suitably treated, have made it possible to make a definite assessment of the structure of these glasses,Accord ing to I. B Grebenshchikov and others, sodium borosilicate glasses consist of a silicate framework which is pre dominantly filled in with sodium borates. The approximate values of the chemically inhomogeneous region It has been postulated that by analogy with the sodium borosilicate glasses, the glasses of other systems also have a microheterogeneous structure. These opinions however have met with a number of objections. The unique dissolution of the sodium borosilicate glasses has been ascribed to the alternating structure of the boron compounds Glass fiber has a very small thickness, a few microns in all, and therefore, when it is reacted with cor roslve substances the individual constituents dissolve fairly quickly, the reagent penetrates into the interior of the fiber, while the destruction products can be almost entirely removed from it. This allows the degrees of cohesion of the separa te constituents within the glass structure to be determined. An investigation of the way that fibers of different compositions dissolve, and their structure after chemical treatment, should give some very valuable information on the structure of glass fiber and of glass. a study of the solubility of sodium borosilicate fiber confirmed that boric and sodium oxides can be oo mpletely removed from it by treatment with acid, whereby a siliceous fiber is produced containing over lo SiOz. In contrast to solid glass, the removal of the sodium borate constituent from the fine fiber takes place without any kind of preliminary heat treatment, and a good deal quicker. This shows that the way in which glasses of a borosilicate composition dissolve is not dependent on the peculiarities of the structure of boron compounds. A silicate fiber can also be produced by the acid treatment of sodium silicate with different contents alkaline metals. Here, the alkaline metals can be quickly driven off from the fiber leaving a silicate fiber containing over 99 Sioz. This shows that the bond between the alkaline metal cations and the silicate frame work is very weak. It can be assumed that when fiber produced from sodium silicate is reacted with acid, an ion exchange of Na* for H+ takes place. On heating the fiber to 500-600.C the moisture is driven off and the pores begin to close. The adsorption The moisture content in the porous fiber corresponds to the quantity of sodium oxide driven off from
CERTAIN CHARACTERISTICS OF GLASS-FIBER AND THE STRUCTURE OF GLASS A. F. Zak Direct methods of structural analysis have not yet enabled a clear conception of the structure of glass m be worked out. Many questions in connection with glass structure are still open to argument. In view of this, great importance is attached to various physic0chemtcal investigations which might throw light upon some individual aspects of this highly complex problem. Among these investigations, the study of glass solubility under the effects of corrosive media is of definite interest. These investigations did not, however, produce the expected results. In the reaction of glass with various agents, the soluble constituents are not entirely eliminated from it, while secondary reactions make it difficult to obtain reliable data on those processes which do take place under these circumstances. To a certain extent, the acid treatment of sodium borosilicate glasses provides an exception. It is well known that when a number of glasses of this system are reacted with acid, the sodium borate constituent is 'almost completely driven off, leaving only the predominantly siliceous framework which contains nearly 96~ SiO~. A method of making products from quartzoid glass which possesses a number of valuable characteristics, has been developed on this basis. Many year's investigation of the structure and properties of sodium borosilicate glasses, both primary and suitably treated, have made it possible to make a definite assessment of the structure of these glasses, Accordlng to I. B Grebenshchikov and others, sodium borosilicate glasses consist of :a silicate framework which is predominantly filled in with sodium borates. The approximate value~ of the chemically inhomogeneous regions have also been defined. It has been postulated that by analogy with the sodium borosillcate glasses, the glasses of other systems also have a microheterogeaeous structure. These opinions however have met with a number of objections. The unique dissolution of the sodium . borosilicate glasses has been ascribed to the alternating structure of the boron compounds. Glass fiber has a very small thickness, a few microns in all, and therefore, when it is reacted with corrosive substances the individual constituents dissolve fairly quickly, the reagent penetrates into the interior of the fiber, while the destruction products can be almost entirely removed from it. This allows the degrees of cohesion of the separate constituents within the glass structure to be determined. An investigation of the way that fibers of different compositions dissolve, and their structure after chemical treatment, should give some very valuable information on the structure of glass fiber and of glass. A study of the solubility of sodium borosilicate fiber confirmed that boric and sodium oxides can be completely removed from it by treatment with acid, whereby a siliceous fiber is produced containing over 99% SiO 2. In contrast to solid glass, the removal of the sodium borate constituent from the fine fiber takes place without any kind of preliminary heat treatment, and a good deal quicker. This shows that the way in which glasses of a borosilicate composition dissolve is not dependent on the peculiarities of the structure of boron compounds. A silicate fiber can also be produced by the acid treatment of sodium silicate with different contents of alkaline metals. Here, the alkaline metals can be quickly driven off from the fiber leaving a silicate fiber containing over 99% SlOg.. This show~ that the bond between the alkaline metal cations and the silicate framework is very weak. It can be assumed that when fiber produced from sodium silicate is reacted with acid, an ion exchange of Na + for H + takes place. The moisture content in the porous fiber corresponds to: the quantity of sodium oxide driven off from it. On heating the fiber to 500-600~ the moisture is driven off and the pores begin to close. The adsorption 608
capacity of the silicate fiber is sharply reduced after this. On heating the acid treated fiber from 200@C or over, although it retains its porous structure, its adsorption capacity is again very low. Porous silicate fiber produced from sodium silicate retains its form and has a very high strength reach Ing 100 kg/mm From this it follows that the basis of glasses from the composition under consideration is a very strong silicate framework consisting of continuously interlinked Sio4 tetrahedra On reaching fibers of a ternary composition which contains up to 12)o tertiary oxides, besides Na2O, with acid, alkali are also driven off from them, but nearly all the tertiary oxides remain in the fiber together with the silica(Fig. 1). The thermostability of these fibers, at a sufficient leaching time in accordance with the structural diagram, is somewhat lower than in quartz fiber. The tertiary oxides CaO, Zno, Bao, PbO, B2O3, TiOz, etc., are fairly firmly bonded in the basic frame work when they are contained in the glass in a small quantity. be assumed that a nunber of oxides (Al2 O3, B2O3, Fe? O3, TiOz, etc. )enter into the basic silicate lattice. The position of the alkaline earth oxides in the structure of glass requires further investigation. On increasing the content of the tertiary oxides, the dissolution haracteristics show a marked change: alkaline metals and the teri ary oxides are simultaneously driven off from the fiber, and with the appropriate acid treatment, only silica remains in the glass, whose Cal content reaches over 99. The silicate fiber produced from these The same results are obtained by the acid treatment of fibers of certain complex compositions containing a large quantity of alkaline earth-, and sesqui-oxides Investigation of the solubility of fine fibers shows that a charac eristic of most silicate glasses is the presence of a silicate framework 10 which governs in many ways a number of the fiber's properties The marked change in solubility on increasing the tertiary oxide Oxide content o content in ternary or certain more complex glasses gives grounds for suming that this causes a profound change in their structure. As in the sodium borosilicate glasses, so in glasses of other systems with a Fig. 1. The influence of various pecific content of various oxides, the existence of regions of different des on the chemical durability chemical compositions which are differently bonded to the main glass e com leO+ SiO2), 20 Na20, framework is possible. reaction with acid The change in the structure of glass, even when the change in its composition is slight, is confirmed by the investigations of the solubil y of zirconium-containing fibers, conducted by Yu. P. Manko. On the acid treatment of sodium-zirconium silica fibers, only predominantly alkaline oxides are driven off from them. But, on introducing boron oxide into the composition of these glasses, the characteristics of their dissolution exhibit a marked change. Besides the alkall, all the remaining oxides pass into the solution in progressively increasing quantities. Already with a 121 B2O3 content in the glass, the fiber becomes dissolved in the acids, whereupon the highly durable oxides- silica and zirconium dioxide pass into the solution. This effect of even a small quantity of B2Og indicates the destruction of the silicate framework of the glass, and the formation of new structural groups which are readily The silicate framework has been characterized to a considerable extent by the results of investigations into he various properties of silicate fiber, Its heat resistance, chemical durability and electrical properties are close to these same properties in quartz, but in contrast to quartz, the silicate fiber if microporous, as a result of which it has a higher sorption capacity. The fiber's soprtion capacity is sharply reduced through a short heating time Certain of its mechanical properties also deteriorate. Its tensile strength is between 2 and 5 times lower than that of commercial fiber made from nonalkaline glass, depending on the composition of the initial fiber and the conditions of its treatment
capacity of the silicate fiber is sharply reduced after this. On heating the acid treated fiber from 200~ or over, although it retains its porous structure, its adsorption capacity is again very low. Porous silicate fiber produced from sodium silicate retains its form and has a very high strength reachIng 100 kg/mm 9, From this it follows that the basis of glasses from the composition under consideration is a very strong silicate framework consisting of continuously interlinked SiO 4 tetrahedra. On reaching fibers of a ternary composition which contains up to 1~o tertiary oxides, besides Na20, with acid, alkali are also driven off from them, but nearly all the tertiary oxides remain in the fiber together with the silica (Fig. 1). The thermostability of these fibers, at a sufficient leaching time in accordance with the structural diagram, is somewhat lower than in quartz fiber. The tertiary oxides CaO, ZnO, BaO, PbO, B~Os, TiO,, etc., are fairly firmly bonded in the basic framework when they are contained in the glass in a small quantity. It may be assumed that a number of oxides (A1203, BzO s, Fe~Os, TiO~, etc.) enter into the basic silicate lattice. The position of the alkaline earth oxides in the structure of glass requires further investigation. 35-- ~ ~ 2o 1o 'qez~176 50 tt 8 12 16 Oxide content % Fig. 1. The influence of various oxides on the chemical durability of glass fiber of the composition 8Gr/o (MeO + SiO2), 20% Na20, on reaction with acid. On increasing the content of the tertiary oxides, the dissolution characteristics show a marked change: alkaline metals and the tertiary oxides are simultaneourly driven off from the fiber, and with the appropriate acid treatment, only silica remains in the glass, whose content reaches over 99~ The silicate fiber produced from these glasses is not so strong. The same results are obtained by the acid treatment of fibers of certain complex compositions containing a large quantity of alkaline earth-, and sesqut-oxides. Investigation of the solubility of fine fibers shows that a characteristic of most silicate glasses is the presence of a silicate framework which governs in many ways a number of the fiber's properties. The marked change tn solubility on increasing the tertiary oxide content in ternary or certain more complex glasses gives grounds for assuming that this causes a profound change in their structure. As in the sodium borosilicate glasses, so in glasses of other systems with a specific content of various oxides, the existence of regions of different chemical compositions which are differently bonded to the main glass framework is possible. The change in the structure of glass, even when the change in its composition is slight, is confirmed by the investigations of the solubility of zirconium-containing fibers, conducted by Yu. P. Man'ko. On the acid treatment of sodium-zirconiumsilica fibers, only predominantly alkaline oxides are driven off from them. But, on introducing boron oxide into the composition of these glasses, the characteristics of their dissolution exhibit a marked change. Besides the alkall, all the remaining oxides pass into the solution in progressively increasing quantities. Already with a 1So B2Os content in the glass, the fiber becomes dissolved in the acids, whereupon the highly durable oxidessilica and zirconium dioxide pass into the solution. This effect of even a small quantity of B20 s indicates the destruction of the silicate framework of the glass, and the formation of new structural groups which are readily soluble in acids. The silicate framework has been characterized to a considerable extent by the results of investigations into the various properties of silicate fiber. Its heat resistance, chemical durability and electrical properties are close to these same properties in quartz, but in contrast to quartz, the silicate fiber if micropomus, as a result of which it has a higher sorption capacity. The fiber's soprtion capacity is sharply reduced through a short heating time. Certain of its mechanical properties also deteriorate. Its tensile strength is between 2 and 5 times lower than that of commercial fiber made from nonalkaline glass, depending on the composition of the initial fiber and the conditions of itc treatment. 609
of ll of particular interest for the study of the structure of glass fiber are the investigations into the deformations ate fibers produced after the acid treatment of fiber of different composition The deformation was studied while the fiber was stretched on a gravimetric dynamometer with a reflec tor elongation reading. Apart from the instantaneous elastic deformation, measurements of the elastic lag were also made, i. e, the elongation of the fiber at different load times As is known, glass and glass fiber have a very high modulus of elasticity and a low elongation. Figure 2 shows the tension curve for aluminoborosilicate fiber which: is characteristic of commercial glasses. Its modulus of elasticity is about 200 kg/mmwhile its breaking strain is 1.50. The elastic lag at maximum load is only 1.7 of the elastic elongation. This deformation characteristic shows that the glass fiber possesses a high degree of stiffness and a low mo bility of its separate molecules. The slight deformation of glass fiber and especially its insignificant elastic lag are not characteristic of substances with a chain structure. Neither is a chain structure revealed through producing especially fine fibers from glass, when glass marbles are drawn out to a factor of tens of thousands. If sufficiently mobile chains had been present in the glass, an orientated structure should have been discernible when a fiber had been formed from it under the appropriate conditions, At the same time, numerous x-ray and microscopic examinations of silicate glass fibers have not disclosed any kind of orientation elements, or any substantial difference between the structures of glass Similar results were obtained in investigations into the most important properties of glass the elastic and plastic deformation, refractive coefficient, and Poisson's ratio chemical durability, electrical conductivity and other properties proved to be identical in glass of different dimensions. The only exceptions are certain mechan ical properties which are governed to a considerable degree by the scale factor. This is explained, not by the orientation of molecules in the fiber, but by the existence of faults which sharply reduce the strength of brittle substances. It is hard to imagine that molecular orientation which arises on drawing thin fibers from glass should have no effect whatever on their properties. Hence, the low deformation of glass fiber and the absence of an orientating effect do not confirm the existence of a chain structure in it. At the same time, the results of investigations conducted by V.v.Tara and his co-workers do show the existence of a chain structure in the silicate framework of a number of silicate glasses. Several other scientists are also of the same opinion, postulating that practical glasses consist of silicate chains and plane lattices of varying dimensions and ramifications. This contradiction is largely explained through the study of silicate fiber deformation. The deformation of silicate fiber produced by the acid treatment of fibers of different compositions is different from the de formation of glass-or quartz fiber, or glass. Its modulus of elasticity is only 1200-3000 kg/ mm2,.e,some 2.5-6 times lower than the modulus of elasticity of aluminoborosilicate fiber. The elastic lag in silicate fibers is many times higher than in glass fibers. It is more than 50 of the elastic elongation, and tens of times greater than the elastic lag in glass fibers(Fig. 2). By virtue of this the silicate fiber is more elastic than glass fiber The deformation of silicate fiber is directly related to the quantity of oxides driven off from the initial fiber. Its deformation steadily increases as the soluble constituents are removed from the fiber(Fig. 3). he high degree of deforma tion of the silicate fiber, and especially its elastic lag, are characteristic of a substance which has a chain structure. This confirms the postulation on the chain structure of the silicate framework. As has been shown earlier, however, such a structure of the silicate framework is not detected in prac tical glasses, and can only be observed after leaching soluble constituents out of them, In our opinion this is due to the fact that in practical glasses, the silicate framework is weighted by separate cations or whole struc tural groups which fill in its interstices and impede the movement of individual chains. As a result the struc ure of the glass becomes fairly rigid and the movement of individual molecules is impeded. But, as the sub stances which fill in the silicate framework are removed, and their cementing action is weakened, its chain
Of particular Interest for the study of the structure of glass fiber are the investigations into the deformations of silicate fibers produced after the acid treatment of fiber of different compositions. The deformation was studied while the fiber was stretched on a gravimetric dynamometer with a reflector elongation reading. Apart from the instantaneous elastic deformation, measurements of the elastic lag were also made, i.e., the elongation of the fiber at different load times. As is known, glass and glass fiber have a very high modulus of elasticity and a low elongation. Figure 2 shows the tension curve for aluminoberosilicate fiber which: is characteristic of commerci~{i glasses. Its modulus of elasticity is about 200 kg/mm 2 while its breaking strain is 1.5%. The elastic lag at maximum load is only 1.7~o of the elastic elongation. This deformation characteristic shows that the glass fiber possesses a high degree of stiffness and a low mobility of its separate molecules. The slight deformation of glass fiber and especially its insignificant elastic lag are not characteristic of substances with a chain structure. Neither is a chain structure revealed through producing especially fine fibers from glass, when glass marbles are drawn out to a factor of tens of thousands. If sufficiently mobile chains had been present in the glass, an orientated structure should have been discernible when a fiber had been formed from it under the appropriate conditions. At the same time, numerous x-ray and microscopic examinations of silicate glass fibers have not disclosed any kind of orientation elements, or any substantial difference between the structure s of glass and fiber. Similar results were obtained in investigations into the most important properties of glass:the elastic and plastic deformation, refractive coefficient, and Poisson's ratio chemical durability, electrical conductivity and other properties proved to be identical in glass of different dimensions. The only exceptions are certain mechanical properties which are governed to a considerable degree by the scale factor. This is exp}ained, not by the orientation of molecules in the fiber, but by the existence of faults which sharply reduce the strength of brittle substances. It is hard to imagine that molecular orientation which arises on drawing thin fibers from glass should have no effect whatever on their properties. Hence, the low deformation of glass fiber and the absence of an orientating effect do not confirm the existence of a chain structure in it. At the same time, the results of investigations conducted by V. V. Tarasov and his co-workers do show the existence of a chain structure In the silicate framework of a number of silicate glasses. Several other scientists are also of the same opinion, postulating that practical glasses consist of silicate chains and plane lattices of varying dimensions and ramifications. This contradiction is largely explained through the study of silicate fiber deformation. The deformation of silicate fiber produced by the acid treatment of fibers of different compositions is different from the deformation of glass- or quartz fiber, or glass. Its modulus of elasticity is only 1200-3000 kg/mm ~, i.e., some 2.5-6 times lower than the modulus of elasticity of aluminoborosilicate fiber. The e}astic lag in silicate fibers is many times higher than in glass fibers. It is more than 50% of the elastic elongation, and tens of times greater than the elastic lag in glass fibers (Fig. 2). By virtue of this the silicate fiber is more elastic than glass fiber. The deformation of silicate fiber is directly related to the quantity of oxides driven off from the initial fiber. Its deformation steadily increases as the soluble constituents are removed from the fiber (Fig. 3). The high degree of deformation of the silicate fiber, and especially its elastic lag, are characteristic of a substance which has a chain structure. This confirms the postulation on the chain structure of the silicate framework. As has been shown earlier, however, such a structure of the silicate framework is not detected in practical glasses, and can only be observed after leaching soluble constituents out of them. In our opinion this is due to the fact that in practical glasses, the silicate framework is weighted by separate cations or whole structural groups which fill in its interstices and impede the movement of individual chains. As a result the structure of the glass becomes fairly rigid and the movement of individual molecules is Impeded. But, as the substances which fill in the silicate framework are removed, and their cementing action is weakened, its chain 610
structure becomes progressively more perceptible. This should be in fact explain the high deformation of the silicate fiber which is produced by means of profound acid treatment through which the substances which fill in the glass framework are removed. Time in min Losses in wt. o 2, Deformation of fiber. 1)Alumino ig. 3. The dependence of the modu borosilicate; 2)silicate. lus of elasticity of fiber on the quanti The chain structure of the silicate framework is also discernible on heating glass fiber. As is known, elastic lag increases considerably in glass fibers as the temperature is raised, especially close to vitrification temperature(Fig. 4). Here the increase in elastic lag occurs simultaneously with the lowering of the viscosity of the glass(Fig. 5). These facts testify to the increase in molecule mobility with the weakening of the cementing effect the oxides which fill the framework. It may be assumed that as the quantity of low-melting constituents in, the glass is increased, or with an increase in the heating temperature, when their viscosity is greatly reduced, the influence of these substances on the silicate framework Is weakened, and its chain structure already becomes noticeably apparent. 20 ep7 Time, hr Flg. 4. The variations in the elastic lag on heating Fig. 5. The elastic lag on varying the vig the fiber cosity of fibers of different compositions. The extensive ramification of the chains and also the cementing effect of the constituents which fill the silicate framework are the main cause of the rigid structure of silicate glasses, and their low deformation
structure becomes progressively more perceptible. This should be in fact explain the high deformation of the silicate fiber which is produced by means of profound acid treatment through which the substances which fill in the glass framework are removed. q00 300, '~ 200 u..... V Z ! ~000 ~ I00 5000 qO00 ".. JOOO e:xo 2000 1000 \ NNN•\ \ 100 200 300 0 10 20 80 Time in min Losses in wt. % ~0 Fig. 2. Deformation of fiber. 1)Alumino- Fig. 3. The dependence of the moduborosilieate; 2) silicate, lus of elasticity of fiber on the quantity of oxides driven off from it. The chain structure of the silicate framework is also discernible on heating glass fiber. As is known, the elastic lag increases considerably in glass fibers as the temperature is raised, especially close to vitrification temperature (Fig. 4). Here the increase in elastic lag occurs simultaneously with the lowering of the viscosity of the glass (Fig. 5). These facts testify to the increase in molecule mobility with the weakening of the cementing effect of the oxides which fill the framework. It may be assumed that as the quantity of low-melting constituents tnthe glass is increased, or with an increase in the heating temperature, when their viscosity is greatly reduced, the influence of these substances on the silicate framework is weakened, and its chain structure already becomes noticeably apparent. r,0 6,17 5,a ' "~ q,o / 3,0 o z,o t.ra I,o _.9.....x -'500' ~00 ~ 3oo~ zoo 01-1 o tao o raa 0 1 2 3 ~ 5 6 0~4 Time, hr 7,0 5 6,0 ~ Z,O 1,0 [,. 9 Fig. 4. The variations in the elastic lag on heating the fiber. Fig. 5 . The elastic lag on varying the viscosity of fibers of different compositions. The extensive ramification of the chains and also the cementing effect of the constituents which fill the silicate framework are the main, cause of the rigid structure of silicate glasses, and their low deformation. 611
Such a glass structure and its relatively high viscosity in the formation region predetermine the absence of an orientation effect when it is drawn into fine fibers. As the constituents which fill the glass framework are re moved or their cementing effect is weakened, the fiber deformation increases sharply, and approaches, in its nature, the defor mation of substances which do have a chain structure Further study of the reaction of fine glass fibers to various agents, and a more thorough study of the struc ture of leached fibers will add to our ideas on the structure of glass THE POLISHING CAPACITY OF SOVIET-PRODUCED ROUGES A. I. Korelova and t. a. makarova Nine rouges from different glass factories were investigated by the cold-working laboratory of the USSR Academy of Sciences Institute of silicate Chemistry, with the aim of comparing the polishing capacity of Soviet-produced rouges. The rouges can be divided according to the method of manufacture, as follows: rouge produced by roast ing, i. e, the products formed through the reaction of green vitriol and soda ash(soda method), the reaction pro ducts of green vitriol and bottoms consisting of iron-bearing waste from chemical production, and also from roasted and unroasted pyrite cinder dust, The chemical composition of the polishing powders and their content of nonacid-soluble inclusions were determined by the conventional analytical chemistry procedures, The amount of quartz particles contained TABLE 1 Chem. comp. o SiO2 Type of rouge Producer factory 日 particle a no Pe,0, Pie cao Mgo999 53 sIze, u 区日 "Dzerzhinskii# 4,932,890,0 18:212 -0,440,23 Proletar 3113:31:1::8131 From pyrite cinder dust Gor'kii 61,636.37|1,18|0,35,0415.9800501015.6<05,471 rom pyrite cinder dust Troitsk 828器(82-1815351:岛 3:389:83esae815an5o 15y of the particles are 100-150p
Such a glass structure and its relatively high viscosity in the formation region predetermine the absence of an orientation effect when it is drawn into fine fibers. As the constituents which fill the glass framework are removed or their cementing effect is weakened, the fiber deformation increases sharply, and approaches, in its nature, the deformation of substances which do have a chain structure. Further study of the reaction of fine glass fibers to various agents, and a more thorough study of the structure of leached fibers will add to our ideas on the structure of glass. THE POLISHING CAPACITY OF SOVIET-PRODUCED ROUGES A. I. Korelova and T. A. Makarova Nine rouges from different glass factories were investigated by the cold-working laboratory of the USSR Academy of Sciences Institute of Silicate Chemistry, with the aim of comparing the polishing capacity of Soviet-produced rouges. The rouges can be divided according to the method of manufacture, as follows: rouge produced by roasting, i.e., the products formed through the reaction of green vitriol and soda ash (soda method), the reaction products of green vitriol and bottoms consisting of iron-bearing waste from chemical production, and also from roasted and unroasted pyrite cinder dust, The chemical composition of the polishing powders and their content of nonacid-soluble inclusions were determined by the conventional analytical chemistry procedures. The amount of quartz particles contained TABLE 1 Type of rouge Soda Vitriol Bottoms From pyrite cinder dust (roasted) From pyrite cinder dust (unroasted) Producer factory Chem. comp. % R~Os F%Oa gitli PesOa CaO MgO "Dzerzhinskii" 97,32 0,44 0.23 /'Avt~176 . . 97,78 0;2 -- ~aoos /'Proletarii" 94,93 2,89 0,04 0,09 1 "Avtosteklo" 91,37 0.m o.33 J"prolotarii" 96,54 1~-31 0.07 0,03 Gor'kii 61,63 6,37 1,18 0,33 l"Proletarii" 79,68 5,34 0,25 0,20 J Irbitsk 9 71,62 2,87 0,57 0,10 9 About 40~,~ 20 of SiO~Darticles are between 15 and 50g 9 * About of the ~phrticles are 50-300g 9 ** About 15% of the particles are 100-150g 9 Z-; ~8 0,15 0,73 1,17 4,02 1,10 5,04 1.41 2,91 2,0~ 100,17i 1,1~ 100,451 1,1~ 100.24] 5,0~ I01,011 I,I~ I00,17 t 5,98 1oo,53 / 3,27 100,15 / 2,42 100,49 / C~0 o = particIe size, ~ OD r00 0.1 <15" ~20 0,6 10-50"* ~2o 1,1 3--6 '00 2,6 10--20 100 1,1 <15 '20 5,6 <10 -- ~,5 425 3,6 <30" m o.~ 7,9 76 3,2 76 5,~ 63 5,1 74 5,8 60 5,4 71 4,7 67 1,8 59 612
