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A series of polyacrylonitrile‐block‐polystyrene (PAN‐b‐PS) and polyacrylonitrile‐block‐poly(methyl methacrylate) (PAN‐b‐PMMA) diblock copolymers with PAN volume fraction up to 20% self‐assembles in nonpolar selective solvents to form cylindrical micelles with a PAN core, having contour length varying between less than 1 µm and tens of micrometers. Micelle characterization by differential light scattering, nuclear magnetic resonance, transmission electron microscopy, atomic force microscopy and differential scanning calorimetry enabled to point out the role played by crystallinity during micellization, thence suggesting that the core crystallization force overcomes other factors governing self‐assembling processes.

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Electron impact (EI) ionization and ammonia chemical ionization (NH(3)/CI) direct-temperature mass spectrometry (DTMS) was used to characterize five natural terpenoid resins: dammar, mastic, colophony, Manila copal and sandarac. Compositional differences were highlighted by the identification of low molecular mass compounds, ranging from di- to triterpenoids, and polymeric components, based on polycadinene and polycommunic acid. Photo-ageing processes occurring under accelerated indoor and outdoor exposure conditions were also investigated. NH(3)/CI and tetramethylammonium hydroxide EI were applied to increase the sensitivity towards highly oxidized molecules. Oxidation and cross-linking reactions were found to affect mostly triterpenoid resins and diterpenoid abietane and pimarane molecules. Oxidation proceeds through a radical mechanism, generally starting from conjugated double bonds. Oxygen atoms are incorporated in the terpenoid structures in the form of alcohols, ketones and carboxylic acids. Oxidized cadinene oligomers released by pyrolytic degradation of the polycadinene fraction of dammar were detected even in unaged samples. Evidence is given indicating the occurrence of cleavages in the cross-linked polycommunic structure of aged sandarac and Manila copal. Bond scissions produce oligomeric fragments based on the communic acid structure and sufficiently volatile to be desorbed at low temperature in DTMS measurements.