Polymerization filling

Properties of Polymerization-Filled Composites and Compositions with Polymerization-Modified Fillers... 

The polymerization filling was effected by the ion-coordination mechanism [17-19]. The monomers were ethylene, propylene, allene, os-butylene, butadiene. The fillers were mineral materials such as ash, graphite, silica gel, glass fibers. The ultimate aim of filler conditioning prior to polymerization is to secure, on its surface, metal complex or organometallic catalysts by either physical or chemical methods [17-19],... 

As a result of polymerization filling a polymer film is formed around some of the filler particles or agglomerates the structure of which depends on the nature of the monomer, method of activation of polymerization, quantity of the polymer formed in the process and other factors. 

Fig. 6. Variation of elasticity modulus (E) under tension and yield strain (es) of the polymer matrix (I, I ) and polyethylene-based composites polymerization filled with kaolin (2,20 in function of polymer MM [320], Kaolin content 30% by mass. The specimens were pressed 0.3-0.4mm thick blates stretching rate e = 0.67 min-1...

Table 10. The strain/stress characteristics of polymerization-filled composites [320, 321]...

On the basis of the recent investigations we can outline two possible ways of creating materials on the basis of polymerization-filled composites ... 

It must be pointed out that polymerization-filled composites with modified fillers may behave in the manner described in [329] where 0.3-3% of PMMA was... 

Table 15. Physico-mechanical characteristics and heats of mixing with chloroform (dH3) of poly(butyl methacrylate) polymerization-filled with aerosil (10% by mass) [333, 334]...

The flow of polymerization-filled composites is, as shown in [338] for composites with chalk coated with copolymer of methyl methcrylate and methacrylate, also largely dependent on the composition of the copolymer and sharply decreases when the percentage of methyl methacrylate in the copolymer increases. 

Gevorgyan MA (1982) Investigation of polymerization-filled polyethylene composites, Institute of Chemical Physics Candidate s thesis... 

Fig. 2. Relationship of conductivity of polypropylene-based polymer composites and filler concentration (natural graphite) 1 — polymerization filling 2 — mechanical mixture [24]...

Polymerization Filling — A Novel Technique for Manufacturing Conducting Composite Materials... 

Quite naturally, novel techniques for manufacturing composite materials are in principal rare. The polymerization filling worked out at the Chemical Physics Institute of the USSR Academy of Sciences is an example of such techniques [49-51], The essence of the technique lies in that monomer polymerization takes place directly on the filler surface, i.e. a composite material is formed in the polymer forming stage which excludes the necessity of mixing constituents of a composite material. Practically, any material may be used as a filler the use of conducting fillers makes it possible to obtain a composite material having electrical conductance. The material thus obtained in the form of a powder can be processed by traditional methods, with polymers of many types (polyolefins, polyvinyl chloride, elastomers, etc.) used as a matrix. 

Natural graphite and synthetic graphite were used as fillers for the manufacture of conducting composite materials by the polymerization filling technique [24, 53-56], The manufacture of conducting polymer composite materials by this technique on the basis of some kinds of carbon black is also known [51, 52],... 

Alternative explanations of the high conductivity of composite materials obtained by polymerization filling are given in works [62, 63] where conductivity higher than that of the graphite proper is attributed to a polymer interlayer between graphite particles, are, in our opinion, insufficiently convincing and cannot explain the whole of the experimental data. 

The liquids contain mainly the monomer MMA in the range 92-99% for silica-filled PMMA and 58% for ATH-filled PMMA. Other liqnid compounds in higher concentration are methacrylic acid and dimethylethylcyclohexene. After distillation, the MMA is pure enough for new polymerization. Filled PMMA yielded more by-products such as long-chain methyl esters and Diels-Alder prodncts. The reason for their formation could be the higher residence time and some catalytic effect of the filler. 

Finally, there are complex fluids that are intermediate between solid and liquid in more than one of the ways listed above. Liquid crystalline polymers (LCPs) are both viscoelastic and liquid crystalline. Ordered block copolymers are viscoelastic and anisotropic. Glassy polymers possess long viscoelastic time scales both because they are glassy and because they are polymeric. Filled polymer melts possess the properties of both polymer melts and suspensions. 

Applications. Numerous uses of x-ray analysis were reported for filled systems. They include orientation of talc particles in extruded thennoplastics, particle size deteimination in nanocomposites, crystallinity of talc nucleated PP, crystallinity of polymerization filled PE, diffraction pattern of filled PVA, structure of nanocomposites based on montmorillonite, degree of filler mixing, structural characteristics of fillers, structure of carbon black filled rubber, the effect of apatite concentration on the structure of wood pulp, and graphite as template. " This list shows the versatility of the method in applications to filled systems. 

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