Swelling limited

Calcium siHcate hydrate is not only variable ia composition, but is very poody crystallised, and is generally referred to as calcium siHcate hydrate gel or tobermorite gel because of the coUoidal sizes (<0.1 fiva) of the gel particles. The calcium siHcate hydrates ate layer minerals having many similarities to the limited swelling clay minerals found ia nature. The layers are bonded together by excess lime and iatedayer water to form iadividual gel particles only 2—3 layers thick. Surface forces, and excess lime on the particle surfaces, tend to bond these particles together iato aggregations or stacks of the iadividual particles to form the porous gel stmcture. 

This process is highly suitable for rubbers with poor solubility. In this process, the rubber sheet is soaked in TEOS or quite often in TEOS-solvent mixture and the in situ sUica generation is conducted by either acid or base catalysis. The sol-gel reaction is normally carried out at room temperature. Kohjiya et al. [29-31] have reported various nonpolar mbber-silica hybrid nanocomposites based on this technique. The network density of the rubber influences the swelling behavior and hence controls the silica formation. It is very likely that there has been a graded silica concentration from surface to the bulk due to limited swelling of the rubber. This process has been predominantly used to prepare ionomer-inorganic hybrids by Siuzdak et al. [48-50]. 

Colloiding of NC s with NG was followed microscopically using crystal violet base to make the process visible by ordinary light. With NC s lower than 11.4%N and higher than 12.6%N., only limited swelling occurred but with NC s betw 11.4 Sc 12.6%N gels were formed which could be seen to diffuse at a speed dependent on the vicosity) E)W.R.Moore, TransFaradSoc 43, 543-52 (1947) Sc CA 42, 3174... 

The extraordinary increases in viscosity exhibited by the semi-continuous latexes with MAA contents of 15, 20 and 25% were attributed to the balance of repulsive forces due to dissociated carboxyl groups with attractive forces due to hydrogen bonds, which results in structure formation extending within the entire system. On the other hand the moderate increase in viscosity of the batch latex was attributed to limited swelling, and moderate interaction between the particles and restricted to the surface regions of the particles. 

Oriented strand board (OSB) is obtained from wood chips. The orientation is designed to simulate the characteristics of a wood panel, with limited swelling and higher resistance in the fibre direction. Chips are orientated by air with a blowing machine. These panels are commonly used on building sites, and they often make part of the walls in houses, especially in the United States. If no orientation is given, the panel is called waferboard. 

Attempts to achieve a more complete recovery of hardwood xylans in this way have not met with success, probably because of the limited swelling power of methyl sulfoxide. Its advantage as an extraction medium for hardwood xylans resides in the fact that it is an organic, neutral (or very slightly basic) solvent which affects neither the 0-acetyl groups nor the glycosidic linkages of the native polymer. 

The mineral adsorbs Cl and NO3 ions poorly and reversibly, whilst S04 is precipitated at the mineral surface. Phosphates are preferentially adsorbed on calcium carbonate. Soils which contain CaCOj show pH values ranging from about 7 to 8.4, due to the formation of calcium hydrogen carbonate. The formation of this compound is accelerated in biologically active soils, with a high production of carbon dioxide. Calcareous soils have a soil solution dominated by Ca + ions, and this limits swelling of soil days and prevents the dispersion of finer particles in the soil. If Ca predominates on the exchange complex of soils, the pH value is maintained above 5.5. 

The number average molar mass of a chain section between two junction points in the network is an important factor controlling elastomeric behavior when is small, the network is rigid and exhibits limited swelling, but when is large, the network is more elastic and swells rapidly when in contact with a compatible liquid. Values of can be estimated from the extent of swelling of a network, which is considered to be ideal but rarely is, and interpretation of the data is complicated by the presence of network imperfections. A real elastomer is never composed of chains linked solely at tetrafunctional junction points but will inevitably contain defects such as (1) loose chain ends, (2) intramolecular chain loops, and (3) entangled chain loops. 

The three-phase coexistence of a balanced microemulsion with oil and water The narrowness (limited swelling) of both the microemulsion and the sponge phase... 

The new polymer co-crystallises with amylopectine from solution. Nucleation and growth of the crystallites, of course, are influenced by the degree of over saturation. The phase diagram of the new polymer, starch and the solvent/non-solvent shows above a critical concentration - the formation of a gel phase that comprises an elastically active network. The network shows limited swelling in water below 140 and it dissolves above this tenqierature. 

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