Shrinkage borosilicate

Because of the fact that organic polymers are known to suffer from swelling or shrinkage on changing the solvent [73,74], the inner wall of the column housings (fused silica capillaries or borosilicate columns) has—prior to polymerization—to be derivatized in order to provide chemical attachment of the monolith rod to the wall. 

Figure 12. Linear shrinkage and skeletal density of a multicomponent borosilicate xerogel during heating in air at 2 °C/min. Skeletal densification accounts for all the shrinkage observed between 250 and 550 °C. (Reproduced with permission from reference 84. Copyright 1986.)...

Figure 5.30 Linear shrinkage and weight loss for a borosilicate gel during heating at a constant rate of 0.5°C/min. (From Ref. 41.)...

Table 5.7 summarizes the dominant shrinkage mechanisms and their relative contribution to the overall shrinkage for the borosilicate gel described in Fig. 5.30. The significant contribution due to skeletal densification by condensation polymerization and structural relaxation should not go unnoticed. 

Table 5.7 Dominant Mechanisms of Shrinkage During the Sintering of a Borosilicate Gel and Their Relative Contrihutions to the Total Shrinkage...

Figure 2-1 Curves for linear shrinkage rate (a) and curves for activation energy (b) in alumina/lead borosilicate glass composites at different programming rates [Ref. 10, 11].

Percent linear shrinkage (solid line) and skeletal density (filled circles) for the multicomponent borosilicate xerogel during heating at 2°C/min. The open circles represent the shrinkage above 150°C that is accounted for by the increasing skeletal density (I45J. 

Shrinkage versus temperature for the multicomponent borosilicate xerogel plotted according to the CHR expression (Eq. 11) 1og(Af//o) versus /TK for three different heating rates [145]. 

Percent shrinkage for the multicomponent borosilicate xerogel in Fig. 39 during heating in air at rates ranging from 0.5 to IS C/min [145]. 

Percent linear shrinkage measured during heating at l C/min for a series of borosilicate gels prepared with varying Na20 contents [130]. The region II-III transition increases from about 525 to 750°C as the NazO content is reduced from 6.3 to Owt /o. 

Linear shrinkage for a multicomponent borosilicate xerogel during heating at 2°C/min in various processing ambients. Dehydration and dealkaiization (CCl., treatment) increase sintering temperature [58],... 

Figure 11. Shrinkage characteristics of (a) CLNT and (b) CLTT ceramics with various borosilicate glasses.

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