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J Ruokolainen

Publications and source records attributed to J Ruokolainen.

4 recordsLinked to original sources
PubMed2003

One-dimensional optical reflectors based on self-organization of polymeric comb-shaped supramolecules.

We demonstrate that complexation of dodecylbenzenesulphonic acid, DBSA, to a diblock copolymer of polystyrene- block-poly(4-vinylpyridine), PS- block-P4VP, leads to polymeric supramolecules PS- block-P4VP(DBSA)y (y = 1.0, 1.5, and 2.0), which self-organize with a particularly large lamellar periodicity in excess of 1000 A. The structures consist of alternating PS and P4VP(DBSA)y layers, where the latter contains smaller internal structure, probably lamellar. The DBSA side chains are bonded to the pyridines by protonation and hydrogen bonding and they effectively plasticize the material. In this way relatively well-developed structures are obtained even without annealing or macroscopic alignment. Transmission and reflectance measurements show that a relatively narrow and incomplete bandgap exists for supramolecules of high molecular weight block copolymer at ca. 460 nm.

Journal Article↗
PubMed1998

Switching supramolecular polymeric materials with multiple length scales

It was demonstrated that polymeric supramolecular nanostructures with several length scales allow straightforward tailoring of hierarchical order-disorder and order-order transitions and the concurrent switching of functional properties. Poly(4-vinyl pyridine) (P4VP) was stoichiometrically protonated with methane sulfonic acid (MSA) to form P4VP(MSA)1.0, which was then hydrogen-bonded to pentadecylphenol. Microphase separation, re-entrant closed-loop macrophase separation, and high-temperature macrophase separation were observed. When MSA and pentadecylphenol were complexed to the P4VP block of a microphase-separated diblock copolymer poly[styrene-block-(4-vinyl pyridine)], self-organized structures-in-structures were obtained whose hierarchical phase transitions can be controlled systematically. This microstructural control on two different length scales (in the present case, at 48 and 350 angstroms) was then used to introduce temperature-dependent transitions in electrical conductivity.

Journal Article↗
PubMed1982

Personality pathology underlying chronic prostatitis.

Personality testing was performed on 56 patients with clinical symptoms of chronic prostatitis. The psychological methods used were RO, TAT, FAM and Beck's Depression Inventory. Q factor analysis of the patients was performed and yielded four factors representing four different personality pathologies, i.e. psychosomatic structure, alexithymic personality, borderline personality and narcissistic personality. The duration of the somatic symptoms correlated positively with the severity of the psychic symptoms. The etiology of the different pathologies expressed by the patients with chronic prostatitis was, according to the researchers, the same. All are disorders of the pregenital level and all can be interpreted as a consequence of disturbance of the first object relationships, the key factor being defective fantasy development.

Adult↗