Adhesive plasticizer functions

Nitto Denko Corporation primarily manufactures industrial adhesive tapes for the electronics, automotive, health care, packaging and construction industries. The company produces industrial, electronic and functional products. Industrial products include double-coated adhesive tapes, masking tapes surface protective materials, sealing materials and label printing systems. Electronics products include LCD-related items general and advanced device resins printed circuit boards and semiconductor package adhesive sheets. Functional products include medical items such as transdermal therapeutic patches polymer separation membranes used for water purification and treatment and plastic engineering products such as information equipment and porous film materials used in cars, electronics, and home appliances. Nitto Denko America, Inc., an optoelectronics subsidiary, manufactures semiconductor... 

Plasticizer-adhesive n. An additive, partly replacing plasticizers, that improves the adhesion of plastics coatings to substrates. For example, polymersable monomers such as diallyl phthalate or triallyl cyanu-rate are added to PVC plastisols to improve their adhesion to metals, but these compounds also contribute to the plasticizing function. 

Pressure-sensitive adhesives seem to possess a critical balance between adhesion and cohesion. The phenomenon of pressure-sensitive tack has been described as a complex function of flow and diffusion. The role of resins in pressure-sensitive adhesives has been interpreted recently as improving tack by a two-step process (1) reducing the modulus and viscosity of the adhesive to give faster, more complete wetting of the substrate and (2) raising the Tg of the adhesive. Plasticizers and solvents accomplish the first objective but not the second This interpretation is consistent with the... 

Goextrusions. In coextmsion, two or more thermoplastic resin melts are extruded simultaneously from the same die. Coextmsion permits an intimate layering in precisely the quantities required to function. Incompatible plastic materials are bonded with thermoplastic adhesive layers. Coextmded films may be made by extmsion-blowing or slot-casting of two, three, or more layers, eg, AB or ABA. Slot-casting is capable of combining up to 11 layers. 

Rheometric Scientific markets several devices designed for characterizing viscoelastic fluids. These instmments measure the response of a Hquid to sinusoidal oscillatory motion to determine dynamic viscosity as well as storage and loss moduH. The Rheometric Scientific line includes a fluids spectrometer (RFS-II), a dynamic spectrometer (RDS-7700 series II), and a mechanical spectrometer (RMS-800). The fluids spectrometer is designed for fairly low viscosity materials. The dynamic spectrometer can be used to test soHds, melts, and Hquids at frequencies from 10 to 500 rad/s and as a function of strain ampHtude and temperature. It is a stripped down version of the extremely versatile mechanical spectrometer, which is both a dynamic viscometer and a dynamic mechanical testing device. The RMS-800 can carry out measurements under rotational shear, oscillatory shear, torsional motion, and tension compression, as well as normal stress measurements. Step strain, creep, and creep recovery modes are also available. It is used on a wide range of materials, including adhesives, pastes, mbber, and plastics. 

Talc is sold for use in a wide variety of appHcations, including paper (qv), ceramics (qv), roofing, paint (qv), plastics, mbber (qv), cosmetics (qv), pharmaceuticals (qv), adhesives (qv), sealants (qv), and animal feedstuffs (see Feeds and feed additives). In all of these appHcations it is a functional ingredient with specific beneficial properties. Talc is rarely used as a filler because it is much more expensive than alternative minerals such as limestone and clay. 

The chelated organic titanates also function as adhesion promoters of the ink binder to printed substrates such as plastic films, paper, and aluminum foil (504). The acetylacetone complexes of titanium are the preferred products for promoting adhesion of printing inks to polypropylene films. 

Functional polyethylene waxes provide both the physical properties obtained by the high molecular weight polyethylene wax and the chemical properties of an oxidised product, or one derived from a fatty alcohol or acid. The functional groups improve adhesion to polar substrates, compatibHity with polar materials, and dispersibHity into water. Uses include additives for inks and coatings, pigment dispersions, plastics, cosmetics, toners, and adhesives. 

Fig. 16. The results of Dyckerhoff and Sell for inlerfacial strengths measured hy butt-tensile tests for various lacquers (adhesives) against various plastics as a function of the surface energy, ys of the plastics. Arrows indicate the surface tensions of the adhesive, y, used in the generation of each curve, showing rough agreement with the requirement that a maximum in adhesion is achieved when yt ys (I kp/cm- 0.1 MPa). Redrawn from ref. [71. ...

Because most plastic bottles are recycled, it is necessary to separate the label and adhesive from the bottle. The label is contaminated with ink and not recyclable. The adhesive is also not recycled. Ideally the adhesive will stick tenaciously to the film, but release cleanly from the bottle during the recycling operation. Adhesives designed to aid in recycling have been developed for this market. They incorporate conventional surfactants in place of some or all of the oil in PSA compositions [69] or use ingredients such as rosin which when neutralized by base can function as surfactants. A goal of the recycling industry is to eliminate the need to use base in the process. 

Chain compositional heterogeneity is of particular relevance to functional copolymers which find widespread use in the coalings and adhesives industries.13,240,246 In these applications, the functional copolymer and a crosslinking agent are applied together and are cured to form a network polymer. The functional copolymers are based on functional monomers with reactive groups (e.g. OH), it is desirable that all copolymer molecules have a functionality of at least two. Nonfunctional polymer will not be incorporated and could plasticize the network or be exuded from the polymer. Monofunctional polymers are not involved in crosslink formation and will produce dangling ends. 

I, After the part is removed from the mold, it is often necessary to perform additional post-lit processing functions on the product. For example, holes may need to be drilled or protrusions cut off to create an opening into a storage tank. Some parts have very thin regions from which the polymer has to be removed, for example the eye socket of a plasticized polyvinyl chloride doll head. Sometimes multiple parts need to be affixed to one another using adhesives or [It. solvent adherents. 

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