Plate curing structure

This reliable control of the curing process allows for stopping the polymerization after gelation, when the system has a fixed three-dimensional structure but is still mbbery and contourable. One potential application for employing the temporal control of the photopolymerization process would be in designing contourable fraction fixation plates. Figure 3(b) are the... 

Materials Description. Three CIBA-GEIGY epoxy/hardener systems were studied Araldite 6010/906, Araldite 6010/HY 917 and Araldite 6010/972 with stoichiometries 100/80, 100/80 and 100/27, respectively. Araldite 6010 was a DGEBA epoxy resin. The hardeners 906, HY 917 and 972 were, respectively, methyl nadic anhydride (MNA), methyltetrahydro phthalic anhydride (MTPHA) and methylene dianiline (MDA). These systems were investigated previously for the matrix controlled fracture in composites (6-8). The curing cycles used can be found in (6). The ideal chemical structures of the systems are shown in Table I. Neat resins were thoroughly degassed and cast into 1.27 cm thick plates for preparation of test specimens. 

Initial experiments showed that the PMDA/ODA material can be successfully cured by a ot plate bake at 280° C for 3 hours. Electrical.Loss tangent data showed that imidization was complete under these conditions. As noted before,the passivation process for bubble devices had to be optimized by using a lower temperature ( to preserve the magnetic properties of the permalloy structures).without losing the electrical insulation characteristics of the final polyimide. IR technique was used as the method of detecting complete cure. A Perkin Elmer 283 spectrometer was used for the IR analyses routinely,and in a few cases the results were checked with a Digilab FTIR instrument.Routine resolutions were 2cm with the Perkin Elmer instrument. Jh s g-dies of imide formation by IR is a well known technique ... 

The above formation current (voltage) algorithm has been developed taking into account the processes that are involved in formation as well as the reaction zones in the plate cross-section where these processes take place. This is only a general algorithm. It should be modified to account for the specific type of plate (automotive, traction, or stationary), size and thickness of plate, type of battery (flooded, VRLA), phase composition, and structure of the cured pastes. 

During the process of curing, a system of pores is created in the cured paste which determines the pore system of the active masses during the subsequent plate formation phase. The pore system is the second element (beside the structure of Pb and Pb02 active masses) that determines the capacity and power performance of the battery. 

Even after recrystallization of 3BS and 4BS is completed, the residual free lead in the cured paste is oxidized and a corrosion layer is formed on the grid surface, the structure of the plate is still mechanically weak. A great number of the paste particles are interlocked through their... 

Figure 9.15 shows SEM micrograph featuring the structure and crystal morphology of the cured paste in the central C zone of the plate after 2 h of soaking in H2SO4 solution of... 

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