J. B. Kinsinger

Expected Square of the Length of Isotactic Vinylic Hydrocarbon‐Type Chains

The mean square length of long isotactic vinylic hydrocarbon‐type chains is calculated. The Markov chain formalism is employed for this calculation. The problem of excluded volume is not considered.

Unperturbed Dimensions of Linear Atactic Polymers

A formalism is developed for calculating the unperturbed dimensions of linear atactic polymers of repeating type (CHR)n and (CH2–CHR)n taking into consideration penultimate effects in the configurational propagation steps and first and second neighbor interactions in the conformational distribution. It is assumed that the configurational and conformational distributions are independent. The calculation has been formalized via the Ising model using a matrix method. The unperturbed dimensions of isotactic and syndiotactic chains are derived as special cases of atactic chains.

Study of Reactivity of a Chain-Bound Molecular Moiety by Intermolecular Exciplex Formation

Abstract The effect of chain-binding on the reactivity of naphthyl groups towards intermolecular exciplex formation with triethylamine has been investigated. Polyamides of 2,6-bis(N-methyl methyl-amino)naphthalene with the diacid chlorides ClOC(CH2)x COCl (x = 2, 4, 6, and 8), designated P-2, P-4, P-6 and P-8, and 2,5-bis(n-methyl N-acetyl methylamino)naphthalene (MC) have been studied. Fluorescence spectra of dilute solutions of the poly-amides and their model compound have been obtained in the presence of varying amounts of triethylamine (TEA) as a quencher. The variations of exciplex monomer fluorescence intensity ratio, IE/IM, with quencher concentration indicates the following reactivity order: MC > P-8 > P-6 ± P-4 > P-2, which reflects the relative diffusion rate and accessibility of the naphthalene moiety. This order also represents the relative chain flexibilities of the polyamides studied. Monomer fluorescence quenching is explained in terms of a scheme involving formation of an exciplex, and a n...