Compatibilizing solvent

Defoamer formulations currently contain numerous ingredients to meet the diverse requirements for which they are formulated. Various classification approaches are possible, including classification by application, physical form of the defoamer, and the chemical type of the defoamer. In general, defoamers contain a variety of active ingredients, both in solid and in liquid states, and a number of ancillary agents such as emulsifiers, spreading agents, thickeners, preservatives, carrier oils, compatibilizers, solvents, and water. 

Figure 4 Elffect of casting solvent on compatibilization studies of NR-PS blend, (a) 0% graft (CHCI3), (b) 1.2% graft (CHCI3), (c) 0% graft (CCI4), and (d) 1.2% graft (CCI4).

One of the earliest references on compatibilizing a nylon-6-polypropylene blend using maleic anhydride grafted PP (PP-g-MAH) was the work of Ide and Hase-gawa published in 1974 [35]. In their study, the formation of a graft copolymer was confirmed by DSC after solvent extraction of the PP component. Blends with PP-g-MAH... 

In contrast to the usual blending of cellulose via a solution medium, a fine-powdered composition was obtained by ball-milling a dry mixture of fibrous cellulose and granulated PEG without any solvent [63]. A certain extent of compatibilization of PEG with cellulose appears to occur even in their solid state, probably by insertion of parts of PEG molecules into the cellulose domains, followed by the formation of hydrogen bonds between cellulose hydroxyls and polyether oxygens. It was shown that such a mechano-chemically prepared powder was moldable three-dimensionally by facile hot-press treatment, e.g., at 120 °C for a composition of CELL/PEG = 80/20 (wt/wt) [64],... 

Surfactant, Compatibilizers and Co-Solvent Assisted CNT-PMMA Composites... 

In the majority of the methods discussed above, CNTs are directly mixed with PMMA using ultrasonication or shear forces. Another approach which has been studied to improve quality of dispersion of CNTs in PMMA is third component assisted dispersion of CNTs (65-67). In this method, a third component such as a surfactant or a compatibilizer is added to assist the dispersion of CNTs in a solvent before mixing with the polymer solution (40). This is an effective non-covalent functionalization technique. 

The wrapping process is typically carried out in liquid medium a PEI chloroform solution (1.5% w/w) is mixed with the SWCNTs under intense stirring. The blend is then treated with an ultrasonic tip for 1 h at 50% oscillation amplitude and 50% cycle time. The resulting dispersion is subsequently filtered using a 0.2 pm pore size PTFE membrane and dried under vacuum at 60°C to assure total evaporation of the solvent. The wrapped SWCNTs can be characterized by different techniques, and some results are included in Table 10.1. Figure 10.5 shows TEM images of acid-treated SWCNTs dispersed in the compatibilizer. Small nanotube bundles shrouded in PEI can be visualized in the micrographs. 

Lecourtier, J. Lafuma, F. Quivoron, C., "Study of Polymer Compatibilization in Solution through Polymer/ Polymer Interactions Ternary Systems Polyethylene oxide)/ Styrene-Methacrylic Acid Copolymers/Solvent," Makromol. Chem., 183,2021 (1982). 

Styrene-containing block copolymers are commercially very important materials. Over a billion pounds of these resins are produced annually. They have found many uses, including reinforcement of plastics and asphalt, adhesives, and compatibilizers for polymer blends, and they are directly fabricated into articles. Most styrene-containing block copolymers are manufactured using anionic polymerization chemistry. However, anionic polymerization is one of the more costly polymerization chemistries because of the stringent requirements for monomer and solvent purity. It would be preferred, from an economic cost perspective, to have the capability to utilize free radical chemistry to make block polymers because it is the lowest cost mode of polymerization. The main reasons for the low cost of FR chemistry are that minimal monomer purification is required and it can be carried out in continuous bulk polymerization processes. 

Block copolymers in selective solvents exhibit a remarkable capacity to self-assemble into a great variety of micellar structures. The final morphology depends on the molecular architecture, tlie block composition, and the affinity of the solvent for the different blocks. The solvophobic blocks constitute the core of the micelles, while the soluble blocks form a soft and deformable corona (Fig. Id). Because of this architecture, micelles are partially Impenetrable, just like colloids, but at the same time inherently soft and deformable like polymers. Most of their properties result from this subtle interplay between colloid-like and polymer-like features. In applications, micelles are used to solubilize in solvents otherwise insoluble compounds, to compatibilize polymer blends, to stabilize colloidal particles, and to control tire rheology of complex fluids in various formulations. A rich literature describes the phase behavior, the structure, the dynamics, and the applications of block-copolymer micelles both in aqueous and organic solvents [65-67],... 

Because the individual blocks in a block polymer exhibit selective solution properties, a block polymer may act as a surface active agent. It can be accommodated at an interface between two phases of other materials if it contains blocks compatible with each phase, respectively. Thus, it can act as an emulsifier between two incompatible solvents, or other liquids. In the same way it can act as a compatibilizer or dispersing agent between two incompatible resins or polymers if these resins or polymers are compatible with the respective blocks. 

Tebol 99. [Arco] t-Butyl alcohol solvent, cosolvent, compatibilizer, coupling agent, processing aid ftn pharmaceuticals, personal care prods., aq. coatings and adhesives, agric. formulations, polymer processing, cleaners/disinfec-tants. 

The effect of the presence of compatibilized incompatible components is apparent in PVC plastisols. Monomeric and polymeric esters are good plasticizers for PVC because they have suitable solubility parameters. A good plasticizer is one which, in sufficient quantity, would almost be a solvent for the polymer. However, a good plasticizer, i.e. solvent, in a plastisol results in a high viscosity composition. This may be unsuitable for slush molding or other applications when low viscosity is desirable. The latter is obtained by adding a secondary plasticizer such as a hydrocarbon oil. In reality, the latter is not a plasticizer but actually a non-solvent which converts the good solvent plasticizer to a poor solvent mixture with resultant decrease in plastisol vis-... 

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