SUMMARY: Polyglycolide (polyglycolic acid, PGA) was prepared by thermally induced solid-state polycondensation from sodium chloroacetate. This reaction leads to a composite of PGA with NaCl, out of which the latter can be extracted by washing with water. A highly porous polymer remains. The course of the reaction was followed by differential scanning calorimetry (crystallinity), X-ray diffraction, NMR spectroscopy and viscosimetry (degree of polymerization), and the polymer was also analyzed by mass spectrometry and mercury porosimetry. The polymer chains grow during the reaction, but prolonged heating leads to a subsequent decrease in chain length due to thermal degradation. The formed NaCl crystals are increasing in size during the reaction. PGA from solid-state reaction is identical with PGA conventionally prepared by ring-opening polymerization, but the molecular weight is smaller (ca. 2 000). No oligomers (like diglycolide) were detected.

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Implemented specifically as a method of theory development, computer simulation allows clarification of a theory and investigation of its implications. Using Petty and Cacioppo's (1986a, 1986b) Elaboration Likelihood Model (ELM), the use of simulation in formalizing a theory, testing the simulation model, and conducting simulation experiments is demonstrated. With formalization of the theory in the form of a block diagram, the entire pattern of causal effects in the ELM core statements becomes visible at a glance. The simulation model was tested through comparing simulated individuals' reactions to stimuli with the experimental and statistical observed reactions of real participants in experiments. The simulation experiments revealed a dynamic attitude shift in dependency on the development of processing intensity.

Zusammenfassung. Die Angehörigen übernehmen den größten Teil der häuslichen Pflege von Menschen mit Demenz. In Anbetracht der wachsenden Zahl der pflegebedürftigen Menschen mit Demenz werden auch assistive Technologien als Unterstützung zunehmend diskutiert. Der Erwerb von Wissen über bestehende technische Systeme sowie von Kompetenzen für die pflegenden Angehörigen bilden dafür die Vorrausetzung.

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