Reference

Modification in the nature of active sites of zeolites A by cobalt(2+) ion exchange

Modification in the nature of active sites of zeolites A by cobalt(2+) ion exchange. Detrekoy, Emil; Kallo, Denes (Cent. Res. Inst. Chem., Hung. Acad. Sci., Budapest, Hung.). ACS Symp. Ser., 40(Mol. Sieves-2, Int. Conf., 4th), 549-58 (English) 1977. CODEN: ACSMC8. DOCUMENT TYPE: Journal CA Section: 35 (Synthetic High Polymers) The isomerization of 1-butene [106-98-9] to cis-2-butene [590-18-1] and to trans-2-butene [624-64-6] and the oligomerization of 2-methylpropene (I) to 2,4,4-trimethyl-1-pentene [107-39-1], 2,4,4-trimethyl-2-pentene [107-40-4], 2,2,4,6,6-pentamethylheptene [63119-56-2], and 1,3,3,5,5-pentamethylheptene [63119-57-3] were carried out in the presence of K-A, Ca-A, Co,K-A, and Co,Ca-A zeolites. The catalytic activity of the zeolites in both reactions is attributed to the Broensted acid OH groups in the partially dehydrated A zeolites contg. divalent ions. Corresponding to its enhanced ability for complexing, the Ca2+ can activate reactive olefin mol., e.g., I. Since the complexing ability of the Co2+ is even higher than that of Ca2+, it can activate the less active olefins, e.g., 1-butene. The replacement of Ca2+ ions by K+ results in nondissocn. of the adsorbed H2O mols. and a decrease in catalytic activity. The difference in the catalytic activity of the fully dehydrated Co2+ and Ca2+ forms in both reactions can be attributed to the effect of 3d electrons of Co2+ on the coordinated olefin mols. The effect of adsorbed pyridine [110-86-1] on the catalytic activity of the zeolites was discussed.

Study of the radical copolymerization of 2,4,4-trimethyl-1-pentene and 2,4,4-trimethyl-2-pentene with maleic anhydride

Study of the radical copolymerization of 2,4,4-trimethyl-1-pentene and 2,4,4-trimethyl-2-pentene with maleic anhydride. Raetzsch, M.; Arnold, M.; Steinert, V. (Inst. Technol. Polym., Dtsch. Akad. Wiss., Dresden DDR-8012, Ger. Dem. Rep.). Acta Polym., 36(1), 8-12 (German) 1985. CODEN: ACPODY. DOCUMENT TYPE: Journal CA Section: 35 (Chemistry of Synthetic High Polymers) Section cross-reference(s): 67 The rate of the AIBN-initiated polymn. of 2,4,4-trimethyl-1-pentene [107-39-1] or 2,4,4-trimethyl-2-pentene [107-40-4] with maleic anhydride (I) [108-31-6], and the max. in the dependence of the overall rate on monomer compn., showed significant differences. Kinetic parameters indicated the copolymn. to be similar to that of I with styrene.