Solution blending Polymerization

A transparent PVC-acrylic copolymer product can be formed by polymerizing 2-ethylhexyl acrylate and acrylonitrile in the presence of a homogeneous solution of PVC using a free radical initiator. In contrast, products formed by the solution blending of PVC and a copolymer of 2-ethylhexyl acrylate and acrylonitrile were translucent to opaque. 

Different polymers have different unique properties. To combine these unique properties of component polymers blending is an attractive means. There are a few methods to make polymer/polymer blends solution blending, melt extrusion, in situ polymerization, among others. Compatibility usually plays a major role in the development of properties. The blends prepared by melt mixing of thermoplastic materials and rubbers have met industrial needs in recent years. 

Composite resins consist of blends of large monomer molecules, filled with unre-active reinforcing filler. As such, they are hydrophobic, which means that they are unable to bond to the hydrophilic prepared tooth surface [1]. Glass-ionomer cements, by contrast, consist of aqueous solutions of polymeric acid, typically poly(acrylic add) and powdered reactive glass. These two components react together in an acid-base reaction, and thus cause the cement to set. These materials are hydrophilic, and therefore capable of wetting the prepared tooth surface and forming tme adhesive bonds. 

Fig. 7. Schematic representation of various methods (Solution blending, melt blending, and in situ polymerization). The delaminated (or exfoliated) and intercalated morphologies are shown.

Composite membranes for fuel cells have been synthesized from sulfonated PAES into which powdered silicotungstic acid was embedded [119]. The sulfonated PAES was synthesized by a direct aromatic nucleophilic polymerization and then solution blended with the silicotungstic acid. 

It has been indicated how interfacial morphology plays a crucial role in the transport properties of hybrid membranes, and conditions as close as possible to the ideal case must be achieved to ensure advanced separation performances. For this reason, several fabrication techniques have been developed to reduce as much as possible the influence of a nonideal interfacial morphology on the transport characteristics of the hybrid membranes. Among the most frequently used procedures there are solution blending, the sol-gel procedure, surface modification, and interfacial polymerization. In some cases a combination of these techniques is required to reach the best dispersion of the filler within the matrix. 

Furthermore, Chen et ol. [14] developed a simple method to prepare PET/MMT nanocomposites without an organo-modifier. Bis(hydroxyethyl) terephthalate (BHET), monomer of PET, was firstly solution blended with MMT to produce the day gallery. The as-prepared BHET-MMT powder was used as the nanofiller for the preparation of hybrids. Then, these powders were mixed with ethylene glycol (EG) and other additives to carry out conventional polymerization. 

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