Minimum film forming temperature

T and are the glass-transition temperatures in K of the homopolymers and are the weight fractions of the comonomers (49). Because the glass-transition temperature is directly related to many other material properties, changes in T by copolymerization cause changes in other properties too. Polymer properties that depend on the glass-transition temperature include physical state, rate of thermal expansion, thermal properties, torsional modulus, refractive index, dissipation factor, brittle impact resistance, flow and heat distortion properties, and minimum film-forming temperature of polymer latex... 

From the electron micrographs, assuming that PVAc particles in the latex are the same size, the formation model of the porous film from the latex film can be illustrated as in Fig. 3 [19]. When the latex forms a dried film over minimum film-forming temperature, it is concluded that PVA coexisted in the latex and is not excluded to the outside of the film during filming, but is kept in spaces produced by the close-packed structure of PVAc particles. 

Minimum boiling azeotropes, 3 802-807 Minimum film-forming temperature (MFFT), 16 291 20 378-379 Minimum film thickness equation, 15 211 Minimum fluidization velocity, 11 793, 797-798... 

Specifications and Standards. Borax stability is an important property in adhesives, paper, and textile applications. Ollier emulsion properties tabulated by manufacturers include tolerance to specific solvents, surface tension, minimum film-forming temperature, dilution stability, freeze-thaw stability, percent soluble polymer, and molecular weight. 

Note MFFT, minimum film-forming temperature. Source Arkema, Inc., 2008 (With permission). 

The application temperature must be maintained above the minimum film forming temperature until the completion of the film formation... 

Minimum film-forming temperature Freeze-thaw stability... 

ASTM D2354 and ISO 2115 Minimum film-forming temperature (MEET). Also, see Table C.l. 

Cellulose acetate is covered by ISO 1157 [80] and minimum film forming temperatures of polymer dispersions by ISO 2115 (81). 

ISO 2115-1996 and equivalent BS2782, method 740C, Polymer dispersions— Determination of white point temperature and minimum film forming temperature. 

At the phenomenological level it may be known that Solvent A works well with acrylic dispersions while Solvent B is better for vinyl dispersions. Experimentally the important question of how much to add can be determined by systematic experimentation. However, for fine tuning some theoretical knowledge about the influence of transient solvent on the glass transition temperature (Tg), and tihe influence this will have on the minimum film forming temperature (MFT) is usefiil. This would undoubtedly lead to some consideration of the distribution (partitioning) of the solvent between the aqueous and polymer phases, which can be... 

Formation of continuous polymer films in mortar or concrete due to a lower minimum film-forming temperature than the application temperature, and the high adhesion of the polymer films to cement hydrates and aggregates. (The minimum film-forming temperature is defined as the lowest temperature at which the polymer particles of a latex have sufficient mobility and flexibility to coalesce into a continuous polymer films.)... 

Film formation in polymer dispersions occurs as a result of the agglomeration and fusion of the polymer particles (diameter lOO-lOOOnm) after evaporation of the water. The minimum temperature at which the particles fuse to form a film (minimum film-forming temperature) is related to the glass transition temperature. It can be lowered to facilitate paint application by adding plasticizers or solvents. 

Film formation occurs via evaporation of water from the paint film and coalescence of the high molecular mass binders the release of water takes place relatively quickly (physical drying). The minimum film-forming temperature depends on the chemical structure of the polymers. Film formation can be facilitated by the addition of organic solvents (e.g., alcohols, butylglycol ethers) or by the action of heat. 

MEET minimum film forming temperature MMD molecular mass distribution... 

Film forming temperature restriction of a coating system Latex systems have minimum film forming temperatures. Below this minimum, the film coating will not properly coalesce to form the film. Also, these coat systems typically become tacky when the temperature is too warm. As a result, process temperatures should be maintained between the extremes of the minimum film-forming temperature and the tackiness point if possible. 

Average particle size [pm] Viscosity [mPas] Minimum film-forming temperature [ Cl pH... 

This effect has a major impact on the use of polymers in aqueous systems. In the case of a polymer in solution, the presence of the solvent plasticizes the polymer during film formation. A polymer with a high Tg, i.e., one greater than ambient temperature, can, when in solution be applied at temperatures below its Tg. In the case of an emulsion polymer, water is a non-solvent in the system and film formation below the polymer Tg is unlikely. The temperature at which a coherent film may be formed from a solution or emulsion based system is known as the Minimum Film Forming Temperature (MFFT or MFT). 

The tensile strength and the elongation-at-break and minimum film-forming temperature were evaluated. The drying oil present in the adhesive film works as a plasticizer. However, changes in the minimum film-fonning temperature were not observed. 

Copolymer composition has a direct effect on the Tg of the polymer, which determines the minimum film forming temperature (MFFT) of the latex and the application. Thus, a 95/5 wt/wt butyl acrylate/methyl methacrylate is an adhesive, whereas a 50/50 copolymer of the same monomers is a binder for paints. Copolymer composition affects properties such as resistance to hydrolysis [4] and weatherability. In situ formed blends of random copolymers of different compositions may be beneficial for application properties [5]. Conventional free-radical polymerization, which is the process used to manufacture almost all commercial emulsion polymers, does not allow the production of block and gradient copolymers (accessible by means of controlled radical polymerization [6], Section 3.3). Nevertheless, graft copolymers are frequently formed, and the extension of grafting largely determines the application properties. Thus, grafting determines the size of the rubber domains in ABS polymers, and the toughness of these polymers increases with rubber size. 

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