Curing formulations

R. Holman, ed., UU andEB Curing Formulations for Printing Inks, Coatings and Paints, SITA Technology, London, 1984. 

Ultraviolet Electron Beam Curing Formulations for Printing Ink, Coating and Paints, 3 Vols., SiTA Technology, London, 1991. 

Single-component epoxy adhesive formulations are the largest type of epoxy adhesives sold, with about 55 percent of the consumption, while two-component formulations account for another 44 percent of the volume. Radiation cure formulations represent the remainder of the market. Epoxy adhesives can also take many forms including solids, solvent-free liquids, solvent-borne systems, and waterborne systems. 

Indeed, photophysical studies by laser flash photolysis combined with the determination of MMA polymerization rate (Rp) in toluene solution, have allowed evaluation of the triplet state lifetime of the above systems, as well as their relative quantum yields of initiation ( j) and a-cleavage ( ). As reported in Table 22, 3, values for poly(MBA) and poly(MBVE) are appreciably lower than those for MBI and MBEE, respectively. On this basis, the polymeric photoinitiators would be expected to display lower activity than the models in the polymerization of acrylic monomers. On the contrary, poly(MBA) and poly(MBVE), together with the related copolymers, show higher values of Rp and hence i, in the UV initiated polymerization of MMA in toluene solution. These findings, therefore, confirm the previously obtained results in film matrix, where a HDDA/BA equimolar mixture was used as curing formulation (Table 21). 

Curing formulation Polymer =100 HAF Carbon Black = 50 Naphthenic Oil = 5 ZnO = 5 S = 2 TMTD = 1 MBT = 0.5 Temp. = 145 °C. S. Table 1 ENB = 5-ethylidene-2-norbornene 1,4-HD = 1,4-hexadiene DCP = dicyclopentadiene MNB = 5-methylene-2-norbomene. Cross-linking reaction rate constant. 

The epoxide moieties of vemonia oil play an important role in making acrylates, groups useful in making UV curing formulations. For instance, the methacrylate ester of vernonia oil is synthesized by reaction with methacrylic acid in the presence of a tertiary amine. The acrylate ester is UV active and is therefore easily polymerized through the acrylate vinyl moieties. The mechanism of making vernonia oil-based acrylates is shown in Figure 15. 

The binders used in these ambient-cured formulations are generally low molecular weight reactive epoxy resins. These are cured with either amine or amine adducts to give the best chemical resistance, or with polyamide to give better water resistance, weathering and recoating properties (Dow Chemical Company, undated a). 

Material for printing on glass can include ceramic glazes, epoxy formulations cured by heat, and UV-curing formulations. The latter two are applied after annealing, as the temperatures applied would destroy these materials. Ceramic glazes are applied before the annealing step and have properties such that the... 

Data on Uvimer 740 Is presented in Table VII, while Uvimers 765 and 775 are compared in Table VIII, Uvlmer 740 is somewhat stiffer and harder than either 765 or 775, primarily due to the difference in the structures of oligomers D and E. It should also be noted that Uvimers 765 and 775 have better color and do not exhibit yellowing on aging. Since the latter two resins employ the same basic oligomer, it is evident that on the basis of viscosity reduction 2-ethoxyethyl acrylate is a more effective diluent than the 2-ethylhexyl acrylate/hydroxyethyl acrylate combination. Thus, it is possible in Uvimer 775, to employ a lower level of reactive diluent and thereby obtain a harder, stiffer, faster-curing formulation. 

Experiments were run to evaluate the effects of low level static (stretch) and dynamic (ultrasonic Irradiation) stress on water permeation of a WRT Neoprene. At the same time, the contribution of a partial silica filler In the place of black was determined. The materials were Identical zinc oxlde-magne-slum oxide-cured formulations except that one contained 30 phr black and the other contained 15 phr black and 15 phr silica. These were molded Into cups with 0.030 In. thick faces and 0.070 In. thick side walls which were then fitted over 3.5X salt water-filled glass cups and sealed with hose clamps. 

As a new family of curing agents, the phenalkamines offer a unique combination of properties making them particularly well suited for ambient temperature cured high solids epoxy coatings. Studies on the reactivity of these curing agents and on the properties of certain cured formulations are presented. Experimental... 

Figure 12. Typical cure formulation for curing phenoxy-containing perfluoroelas-tomer with bisnudeophiles...

Information about the state of cure, formulation errors, and changes in processing parameters is obtained at aU intermediate stages, from the raw material to the finished product. 

The experimental work presented in this paper is intended to show the utility of AM oligomers in UV cure formulations and the effect combined acrylamide content has on the UV cure properties of acrylated melamines. This work will consider three cure processes UV, thermal, and dual cure. In this case dual cure is UV followed by a thermal bump. 

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