✍ Scribed by Engel, Dieter ;Schulz, Rolf C.
No coin nor oath required. For personal study only.
The anionic homopolymerization of 2‐isoprenylnaphthalene with butyllithium in tetrahydrofuran at –78°C is described. The refractive index increment amounts to d__n__/d__c__ = 0,2084 ml/g for these polymers in toluene at 25°C and wavelength λ = 436 nm. Determination of the molecular weights by light scattering yielded values between 13 000 and 270 000. The second virial coefficients also determined by light scattering measurements are comparable with the corresponding data of poly(α‐methylstyrene). A calibration curve is given for gel permeation chromatography of the poly(2‐isoprenylnaphthalene)s, whose polymolecularity indexes M~w~/M~n~ lie between 1,06 and 1,2. Their intrinsic viscosity/molecular weight relationship is [η] = 1,43·10^−2^ M^0,663^. From ^1^H NMR of the α‐methyl group fractions of isotactic triads between 30 and 55% are evaluated. The glass transition temperature extrapolated to infinite molecular weight is T~g∞~ = 221°C. Above 300°C fast degradation by monomer formation is observed.
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