Surlyn

Tobolosky suggestion of crystalline and amorphous polyolefin copolymers Commercial PU elastic fiber, DuPont Commercial PU TPEs lonomeric TPE, DuPont (Surlyn)... 

The linkage between two chains can also be ionic. Thus the copolymer between ethylene and methacrylic acid (MA) (up to 15% MA), made by free radical polymerisation, yields a polymer with pendant carboxyl groups. Neutralisation with zinc ions gives a crosslinked, thermo-reversible polymer (Surlyn ). The resulting polymer (ionomer) has limited properties, although it is the favoured material for the outer covering of golf balls. 

Fascia of the Dodge Neon made out of supergloss Surlyn alloy (DuPont). 

The stiff regions observed in the studies of McLean et al. were assigned to fluorocarbon crystalline domains, the size of which was around 10 nm. The crystalline packing was referred to as lamellae which are not organized into stacks, as is the case for the Surlyn ionomers that were studied. An interesting outcome of the normal tapping studies was the discovery of a very thin ( 5 A) fluorine-rich layer over the surface in which the contrasted soft regions are amorphous. 

Surlyn A (ER-1552) Ethylene-methacrylic acid random copolymer neutralized with sodium ion E. I. du Pont de Nemours Co., Inc. 

The Surlyn A ionomers (E. I. du Pont de Nemours Co.) are believed to be derived from copolymers of ethylene with minor amounts of methacrylic acid which are treated subsequently, so that substantial amounts of the carboxylic acid are converted to the sodium or other metal carboxylate. Resins similar to the one studied in this work contain about 10 weight % methacrylic acid. The ash (sodium carbonate) indicates about 40% neutralization. This resin, which contains 0.05% Santo-white Powder (Monsanto Chemical Co.), a phenolic antioxidant, is of medium molecular weight—i.e., probably corresponding to an ethylene homopolymer with a melt flow index around 20 (17). The molecular weight distribution is broad (17). 

In several instances 0.5-mm. thick sheets of Surlyn A were hung over concentrated aqueous hydrochloric acid in a desiccator for about one week, then dried in vacuum and irradiated. Infrared examination of thin films conditioned in this way for 3 days indicated little or no increase in crystallinity x-ray examination indicated the presence of small amounts of crystalline sodium chloride. 

Gel Fraction. As in previous work (23), a modified Charlesby-Pinner technique was used. However, reproducible gel fractions from Surlyn A samples were only obtained if a slow stream of gaseous hydrogen chloride was passed through the extracting solvent for several hours during the third extraction. 

We did not measure a mixture of the Phillips experimental polymer with Surlyn A itself since phase contrast microscopy indicated that the former had segregated as a separate crystalline phase. However, the differential absorbance at 10.35 microns of a Surlyn A sample irradiated to a 50-megarad dose decreased only 6.0% after sample and reference were exposed to HC1 for 2 weeks. Furthermore, the rate of trans-v inylene growth with dose in Surlyn A was sensiblv unaffected by prior exposure to HC1. 

Physical Properties. Figure 1 shows the variation of tensile strength at room temperature with radiation dose for Surlyn A, untreated and treated with hydrochloric acid, and a low (DFD 6040) and high density... 

Figure 3 shows the variation of elastic modulus at 160 °C. with dose for these samples. In the case of Surlyn A, untreated or treated with HCl, and DFD 6040, heating for 30 minutes at 100°C. after irradiation had no significant effect on the modulus. The figure, therefore, shows only... 

In view of the similarity in behavior of the networks in the ionomer and low density resin, we are able to deduce from modulus and elongation at rupture measurements the relative crosslinking rates. It appears that Surlyn A crosslinks 50 to 60% more rapidly than DFD 6040. The increased crosslinking in the ionomer may be associated with the radio-... 

EPFL [15] N3 800 W m-2 Xe lamp UV cut off TBAI, I2 in AN Surlyn + waterglass 100 days Jsc increased and Voc decreased for the first 20 days. The efficiency is constant for 100 days... 

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