Surlyn sealant

Several organic sealants such as epoxy resins, butyl rubber or silicones prove to be more or less permeable and the tiny amount of solvent in the cell is rapidly lost. Suitable organic sealing materials for this technology turn out to be thermoplastic materials, like polyethylene/carboxylate copolymers. So far, Surlyn 1702 ionomer from Dupont has been the main substance used to optimize cell performance and build module prototypes. However, the softening point of Surlyn is rather low (65° C) and at elevated temperatures (> 70°C), serious solvent loss is observed because the bond between Surlyn and TCO-coated glass is substantially weakened [7]. 

Fig. 7.9. Efficiency data for two test cells (active area 4 cm2) exposed to outdoor conditions for 1 year. The efficiencies of the cells were measured from time to time with an indoor solar simulator. The dye used is Ru(NCS)2(2,2 -bipyridyl-4,4 -dicarboxylate)2 (N719). 0.6 M hexylmethylimidazolium iodide (HMII), 0.1 M Lil, 0.05 M I2, 0.5 M tert-butylpyridin (TBP) in propionitril was used as the electrolyte. Surlyn 1702 (Dupont) was used as the sealant. The cells were placed under a window to protect them from rain. Test location INAP, Gelsenkirchen, Germany...

Absorption of d-limonene by the different sealant films during storage at 24°C, 49 RH is shown in Table 3- Within 3 days storage, all of the films had rapidly absorbed d-limonene. After 3 days, the rate of absorption in LDPE and Surlyn (sodium type) decreased, while Surlyn (zinc type) had reached saturation. 12 and 18 days were required to reach saturation for Surlyn (sodium type) and LDPE respectively. Thg amount of d-limonene absorbed at equilibrium was 6.4 mg/100 cm for Surlyn (zinc type). The carboxy and zinc groups in the Surlyn probably alter the lipophilic character of the polymer, but do not prevent absorption of flavor components. 

Primers can be used on foil also, but another approach often used with foil is to use a polymer that has polar groups on the chain, such as an acid copolymer or an ionomer, for the coating. Polyethylene acrylic acid is a typical acid copolymer, lonomers, as discussed in Section 4.1.4, are partially neutralized acid copolymers, of which Surlyn is the best known. Acid copolymers and ionomers can also be used as sealant layers. 

Mylar M34. Designed to be reverse printed on the coated side, then combined with a sealant layer such as polyethylene or Surlyn resin—locking in the PVDC coating. Such a structure is quite durable, and its sparkling clarity and excellent barrier properties, plus its... 

Ethylene ionomers, such as Surlyn from DuPont , have been the premium sealant materials for packaging applications due to their excellent seal strength and process robustness. The ethylene ionomers achieve the unique property characteristics through the development of a network morphology. In this paper the development of new ethylene ionomers will be discussed. The versatile compositions and the unique morphology of the new ionomers will be presented together with the novel gas permeability properties. Their enhanced breathability to oxygen, carbon dioxide, moisture, etc., selective permeability, and smart barrier properties will be presented. 

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