Sizing glass fibers

A portion of the white film from each package was heated in TCB containing 0.1% w/v of N-phenyl-2-naphthylamine as an antioxidant. The portion of the white film not covered by the label was sampled for the "bad" package sample. The "good" packages had no label. The nominal polymer concentration in solution was 2 mg/mL. The samples were filtered hot through 0.5-pm pore size glass fiber filters. TCB is a non-solvent for PET. Therefore, only the PE and EVA layers were dissolved. The middle PE layer accounted for about 80% of the film thickness. PET and EVA were minor components of the film. 

In pultmsion process, thermoplastic polymer is deposited between multifilaments. The polymer comprises additives which do not adversely affect activity of catalyst of covalent bond formation between mnltifilaments and polymer coating. Talc was found to be snitable nncleating agent. Talc is also used in pnltmsion process of sizing glass fibers. ... 

Hardness of poly(3-hydroxybutyrate) containing disulphide nanotubes increases on small addition and then levels ofll or even decreases. " The increase is explained by increased crystallinity and reduced spherulite size. Glass fiber composites of polypropylene have higher hardness when glass fiber is treated with silanes and has better interfacial adhesion with matrix polymer. " Hardness of PA-66 composite nucleated with 1 wt% carbon fiber increased four-fold. With exception of the effect of carbon fiber it is difficult to differentiate between nucleation and reinforcement, especially considering that the effects are caused by inorganic particulates. 

Four techniques were used to characterize the surface of bare (sample 1) and sized glass fibers (39). The sizes include cationic silane (sample 2), polyethylene dispersion (sample 3), silane/polyurethane dispersion (sample 4), and silane/ep-oxy dispersion (sample 5). Sample 2 shows highest surface free energy by capillary rise method. There is almost 30 mJ/m difference between samples 2 and 4. However, the difference in surface free energy among five samples is nonexis-... 

The wetting kinetics of sized glass fibers by melt changed due to acid-base interactions and compatibility between the film former and surrounding bulk polymer matrix. The highest interfacial shear strength values corresponded to the... 

Pike S.M. and Moran S.B. 1997. Use of Poretics (super R) 0.7 jun pore size glass fiber filters for determination of particulate organic carbon and nitrogen in seawater and freshwater. Mar. Chem. 57 355-360. 

Urethanes Urethane adhesion promoters are used widely to bond PVC to polyester, nylon, and other fabrics, including sized glass fiber. In multicoat operations, the additive is used only in the first coat. With, polyester fabric, the isocyanate component in urethane formation can be used alone. Solvent or plasticizer solutions of oligomerized toluene diisocyanate (TDl) are available under the trade names Vulcabond (Akzo Nobel), Vanchem HM-50 (Vanderbilt), Thanecure T9 (TSE Industries), and Desmodur (Bayer). For improved resistance of the bond to heat and moisture, products based on bisphenyl diisocyanate (MDl) are also used. These include Vanchem HM-4346 and Rubinate 9480 (Huntsman). These are typically used at 3-7 phr levels in plastisols for coating polyester fabric. The second or subsequent coats should contain titanium dioxide and UV light stabilizer for outdoor service. With translucent products, an aliphatic isocyanate such as Desmodur N-lOO or TMl META (Cytec) should be used. 

Again, the relative diffusion coefficient (D sID) is independent of D and of the cylinders size. As in the case of the spheres, it doesn t matter whether the cylinders are carbon nanotubes or millimeter-sized glass fibers the only variable is their volume fraction. The change in diffusion for cylinders is smaller than that for spheres but only slightly. The continuous phase still dominates diffusion. 

In the spray-up process a reinforcement, usuaHy glass fiber, is substituted for the mat and a special spray gun simultaneously chops the glass fiber and appHes it with catalyzed resin to the mold surface. Hand rolling techniques then consoHdate the fiber and resin to conform to the mold surface contours. The shorter chopped fibers aHow for more intricate design detaHs than do mats. Both processes rely heavily on the operators skiHs for product quahty. These two processes require the least capital investment and have the largest product size capabHity of aH the processes. A single-surface mold produces a part with one controHed (usuaHy the visible) surface. 

Reinforced Thermoplastic Sheet. This process uses precombined sheets of thermoplastic resin and glass fiber reinforcement, cut into blanks to fit the weight and size requirements of the part to be molded. The blanks, preheated to a specified temperature, are loaded into the metal mold and the material flows under mol ding pressure to fiU the mold. The mold is kept closed under pressure until the temperature of the part has been reduced, the resin solidified, and demolding is possible. Cycle time, as with thermosetting resins, depends on the thickness of the part and the heat distortion temperature of the resin. Mol ding pressures are similar to SMC, 10—21 MPa (1500—3000 psi), depending on the size and complexity of the part. 

The bonding properties of (Ti02) have been used for size-reinforcing of glass fibers so that they adhere to asphalt or to a PTEE—polysulfide mixture to impart enhanced flex endurance (434—436). Poly(vinyl alcohol) (PVA) solutions mixed with sucrose can be cross-linked with the lactic acid chelate and used generally for glass-fiber sizing (437). 

The flow along the membranes also improves the mass transport there, and the separators between the membranes are constmcted to provide good flow distribution and mixing on the membrane surfaces. Membrane sizes are often about 0.5 x 1 m, spaced about 1 mm apart. Many types of polymers are used to manufacture these ion-exchange-selective membranes, which are often reiaforced by strong fabrics made of other polymers or glass fibers. 

In recent years, prices for natural fibers were not stable, especially for flax fibers. Flax fibers, showing the highest values for strength (Table 2), are about 30% more expensive than glass fibers. Additionally, is price depends on the fiber preparation. Usually, glass fibers are delivered pretreated, i.e., treated with different sizes... 

In investigations of the failure of fiber compositions (PETP — short glass fibers) [251] it was found that the main process responsible for composite failure under load is the rupture at the matrix-fiber interface. The author of [251] observed formation of microvoids in loaded samples, both at the interphases and in the bulk. The microvoids, or cavities) grow in size and become interconnected by microcracks, and this results in fiber separation from the binder. However, when the matrix-fiber bond is strong enough, the cavities appear mostly in the bulk of matrix, the failure of the specimen does not over-power cohesion and traces of polymer remain on the fibers. 

Reduced Mold Shrinkage (Increased mold-to-size capability) Glass fibers Carbon fibers Fillers Ductility, cost Ductility, cost Tensile strength, ductility, cost Ductility, cost Ductility, cost Tensile strength, ductility, cost... 

During operation, samples of all flows were taken for suspended solids analysis. These tests were performed by a qualified local analytical laboratory. Procedures for this analysis were as outlined in standard methods.47 Glass fiber filter pads with a particle size retention of 1.2 pm were used. 

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