Pasa Jell

I08J (in a different form than for aluminum adherends) but Pasa Jell 107, Turco 5578 and alkaline peroxide [80] etches are also popular. 

Step Pasa Jell 107 Alkaline peroxide Turco 5578... 

Pasa-Jell treatment Pasa-Jell 107 and 107M are proprietary blends of acids, activators, surfactants, inhibitors, and thickening agents, marketed by Semco Sales and Services of California. Surface preparation... 

Pasa Jell is a trademark of Semco, Glendale, Calif. 

T. J. St. Clair (MASA Langley Re6eaAch CentoX) The PASA-JELL 107 method was used for cleaning all of adherends used in the presented work. The phosphate-fluoride treatment was studied in our lab and was found to give the same lap shear results at room temperature on the systems that were tested. 

Panels of Ti-6-4 alloy adherend were obtained from the NASA-Langley Research Center. The panels were either used in the as-received condition or cleaned by the Pasa-Jell 107 method, a commercial process (American Cyanamid ) for cleaning titanium alloy surfaces. The primary steps in this cleaning process are, briefly sample immersion in degreasing 1,2-Tdichloroethane immersion in an alkaline cleaner, SPREX AN 9 solution pickling in an HNO3/HF solution and treatment with Pasa-Jell 107 (a chromate based acid paste). 

NASA-Langley Research Center. The characteristics of the samples in the two sets are given in Table I. The first set of samples were lap-joints of Pasa-Jell cleaned Ti-6-4 panels bonded with one polyimide resin adhesive. The resin adhesive was prepared from benzophenone tetracarboxylic acid dianhydride (BTDA) and m,m -diaminobenzophenone (m,m DABP). The structures of these compounds are given in Table II. The uncured adhesive was applied on the adherend in the polyamic acid stage from either diglyme or DMAC solution and then heat cured to the polyimide resin form. This condensation polymerization reaction is shown below. 

Five samples were cut from a bare Ti-6-4 panel. One sample, which served as a control, received no pretreatment and was placed into a vial. The Pasa-Jell cleaning process was applied to the four remaining samples. A sample after each step of the cleaning process was blown dry in a nitrogen stream and placed into a vial. Exposure time of the freshly cleaned material to the lab atmosphere was kept to a minimum. These five samples were examined in the scanning electron microscope. 

Materials. Distilled water was obtained from a Bamstead metal still. Mercury was obtained from the Glass Shop at the Virginia Polytechnic Institute and State University. Aldrich (99%) bis(2-methoxy ethyl) ether and octane were used. Dimethylacetamide (DMAC) was obtained from Burdick Jackson (technical grade) and was distilled from calcium hydride. The degreaser used was 1,2-dichloro-ethane obtained from Fisher (ACS Certified). Metal coupons of the Ti-6-4 alloy (2.5 x 12 cm), and solutions of Pasa-Jell 107, HNO3/HF, and SPREX AN 9 were furnished by the NASA-Langley Research Center. 

IR reflectance spectra were obtained for the fractured samples of Set II. The samples were placed in the reflectance attachment so that the lapped portion of the panels covered the entire sample window. This method allowed spectra of the samples to be obtained in situ. Comparisons of intensities of individual peaks in the different sample spectra proved to be unsatisfactory in evaluating the amount of adhesive present on a panel. For this reason, reflectivity as measured by percent transmission in a non-absorbing region (2600 cm ) was considered as a possible characterization of the fracture surface. The percent transmission in this region was measured for each sample and also for a polished Ti-6-4 surface and a Pasa-Jell cleaned Ti-6-4 surface. 

The cut samples were secured to the ESCA probe with double-sided tape. ESCA spectra also were obtained for Ti-6-4 samples in the as-received condition and cleaned by the Pasa-Jell method, and coated with the polymer resin. Two polymer coated samples were prepared by placing a 0.01 ml of 14% and 25% dilutions in diglyme of the stock resin solution of BTDA and m,m DABP on cleaned Ti-6-4 panels. Each drop spread spontaneously over the entire sample surface. The samples were dried at room temperature for at least 24 hours prior to the ESCA and contact angle runs. 

A. J. Kinloch (JiivuJ>i/iy 0 VQ. Q.n62, U. K.) It has been suggested that the type of oxide on the titanium alloy surface, for example whether it is rutile or anatase, can affect the water resistance of the subsequently made joint. Did you conduct any experiments, for example x-ray diffraction analysis, to identify the structural type of titanium oxide formed by your Pasa-Jell surface pretreatment ... 

D) Surface treatments with Pasa Jell 107 can also be used (SemCo Div., PRC). 

Pasa Jell 107 surface treatment bonding conditions, 400°C, 1000 psi, 15 minutes. 

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