Polymer static bulk

Homopolymerization of macromonomer provides regular star- or comb-shaped polymers with a very high branch density as shown in Fig. 1 a,c,e. Such polymacromonomers, therefore, are considered to be one of the best models for understanding of branched architecture-property relationships. Their properties are expected to be very different from the corresponding linear polymers of the same MW both in solution and the bulk state. Indeed, during the past decade, remarkable progress has been accomplished in the field of static, dynamic, and hydrodynamic properties of the polymacromonomers in dilute and concentrated solutions, as well as by direct observation of the polymers in bulk. 

There are large differences between the level of static adsorption of HPAM and dynamically retained level in a core or pack (Lakatos et al., 1979). These differences are the result of changes in the specific surface area of consolidated and unconsolidated packs and also the accessibility of certain portions of the pore space. These differences also depend on the extent of mechaifical retention that is present in the dynamic core flood experiment. Polymer retention in consolidated porous media cannot be determined with static bulk adsorption (batch adsorption techniques) because the process of disaggregation to obtain... 

Experiments under static conditions with phase distribution of CaCl2 and HCl taken at unequal proportions of the two components in the initial mixture support the above interpretation of the situation. Thus, small amounts of HCl, 0.6 N, cannot cause a significant additional exclusion of 4 N CaCl2 from the porous space of the polymer into bulk solution. The distribution coefficient of the salt drops from 0.75 to 0.72, only, while HCl itself experiences a very strong influence from the major mixture component and its distribution coefficient increases from 1.0 to 2.6. Vice versa, if the initial mixture contains more HCl (3.84 N) than CaCl2 (0.50 N), the k value for the former increases from 1.0 to 1.13, only, while the impact of HCl on the minor component, CaCl2, is more significant k value for the latter drops from 0.75 to 0.51. 

Kenics-type static mixers have been used as inserts in tubular reactors. Compared to an open tube operated at the same pressure drop, the static mixer gives about 40% more heat transfer. Stand-alone mixer reactors of the Koch or Sultzer SMR type have been used as post-reactors and devolatilization preheaters. The polymer flows through the shell side of the SMR and the heat transfer fluid flows inside tubes that have been strategically placed to promote radial mixing of the polymer. One bulk polystyrene process used the SMR as in a recycle loop as the first reactor, but the capital cost is high compared to alternatives such as a boiling CSTR or a proprietary stirred-tube reactor. 

Both polymer and the nanofiUer are introduced simultaneously into a melt mixing device (extruder, internal mixer, etc.). This process involves annealing a mixmre of polymer and nanofiller above the softening point the polymer, statically or under the shear. During annealing, the polymer chains diffuse from the bulk polymer melt into the galleries between the nanofrller layers (Liu et al. 2012 Sinha Ray and Okamoto 2003). 

Bishop M, Ceperley D, Frisch FI L and Kales M FI 1980 Investigation of static properties of model bulk polymer fluids J Chem. Phys. 72 3228... 

In a molded polymer blend, the surface morphology results from variations in composition between the surface and the bulk. Static SIMS was used to semiquan-titatively provide information on the surface chemistry on a polycarbonate (PC)/polybutylene terephthalate (PBT) blend. Samples of pure PC, pure PBT, and PC/PBT blends of known composition were prepared and analyzed using static SIMS. Fn ment peaks characteristic of the PC and PBT materials were identified. By measuring the SIMS intensities of these characteristic peaks from the PC/PBT blends, a typical working curve between secondary ion intensity and polymer blend composition was determined. A static SIMS analysis of the extruded surface of a blended polymer was performed. The peak intensities could then be compared with the known samples in the working curve to provide information about the relative amounts of PC and PBT on the actual surface. 

Snow crystals [4] Their macroscopic structure is different from a bulk three-dimensional ice crystal, but they are formed by homologous pair-pair interaction between water molecules and are static and in thermodynamic equilibrium. It should be noted, however, that dendritic crystal growth is a common phenomenon for metals [5-7] and polymers. The crystals grow under non-equilibrium conditions, but the final crystal is static. 

Since the possibility of direct melt intercalation was first demonstrated [11], melt intercalation has become a method of preparation of the intercalated polymer/ layered silicate nanocomposites (PLSNCs). This process involves annealing, statically or under shear, a mixture of the polymer and organically modified layered fillers (OMLFs) above the softening point of the polymer. During annealing, the polymer chains diffused from the bulk polymer melt into the nano-galleries between the layered fillers. 

PTT fibers and yams have bulk, resiliency, stretch-recovery, softness, hand and drape, properties which are similar to those of nylons and much better than those of PET. Such materials are inherently resistant to most stains which are acidic in nature because they not have dye sites. They also have a lower static propensity than nylons. PTT fibers are dyed with disperse dyes but at a lower temperature than PET because of the polymer s lower Tt. The combinations of these properties are attractive to carpet and textile manufacturers in some applications where PTT could replace nylon or PET. PTT also offers the potential of creating new fiber products by using the unique combinations of these properties not found in either nylon or PET alone. 

A continuous bulk polymerization process with three reaction zones in series has been developed. The degree of polymerization increases from the first reactor to the third reactor. Examples of suitable reactors include continuous stirred tank reactors, stirred tower reactors, axially segregated horizontal reactors, and pipe reactors with static mixers. The continuous stirred tank reactor type is advantageous, because it allows for precise independent control of the residence time in a given reactor by adjusting the level in a given reactor. Thus, the residence time of the polymer mixtures can be independently adjusted and optimized in each of the reactors in series (8). 

This sieve effect cannot be considered statically as a factor that only determines the amount of accessible acid groups in the resin in such a way that the boundary between the accessible and non-accessible groups would be sharp. It must be treated dynamically, i.e. the rates of the diffusion of reactants into the polymer mass must be taken into account. With the use of the Thiele s concept about the diffusion into catalyst pores, the effectiveness factors, Thiele moduli and effective diffusion coefficients can be determined from the effect of the catalyst particle size. The apparent rates of the methyl and ethyl acetate hydrolysis [490] were corrected for the effect of diffusion in the resin by the use of the effectiveness factors, the difference in ester concentration between swollen resin phase and bulk solution being taken into account. The intrinsic rate coefficients, kintly... 

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