Mechanochemical amorphization of chitin: impact of apparatus material on performance and contamination

• Thomas Di Nardo and
• Audrey Moores

Beilstein J. Org. Chem. 2019, 15, 1217–1225, doi:10.3762/bjoc.15.119

• range of Vickers hardness values and the impact of these parameters is discussed. The role of the size and mass of the balls is also studied in the case of stainless steel. This study also highlights one of the major challenges during milling, which is contamination of the studied samples. Keywords

• composition with either a diameter of 9.5 mm or mass of approximately 2 g. We could determine that Vickers hardness is a key parameter determining the ability to perform amorphization of biomass materials especially when considering efficient kinetic energy transfer [59]. Finally, the effect of materials

• hardness values. We retrieved Vickers hardness values from material specification sheets to correlate amorphization performance with them (Figure 1). With the 2 g ball series, a clear trend can be seen. A crossover point exists where all materials of Vickers hardness larger than the one of chitin itself

Synthesis of a resin monomer-soluble polyrotaxane crosslinker containing cleavable end groups

• Ji-Hun Seo,
• Shino Nakagawa,
• Koichiro Hirata and
• Nobuhiko Yui

Beilstein J. Org. Chem. 2014, 10, 2623–2629, doi:10.3762/bjoc.10.274

• prepared resin monomer-soluble PRX crosslinker was successfully polymerized with a mixture of HEMA and UDMA to provide photosetting plastic. It was confirmed that the Vickers hardness of the prepared plastic was greatly decreased after treatment with dithiothreitol. This indicates that the resin monomer

• -soluble PRX crosslinker can be applied to design degradable photosetting plastics potentially used in the industrial or biomedical field. Keywords: α-cyclodextrin; composite resin; disulfide; polyrotaxane; Vickers hardness; Introduction Polyrotaxane (PRX) is a supermolecule containing host molecules

• the change of hardness was estimated by means of the Vickers hardness test. As shown in Figure 4, the initial Vickers hardness of the hardened plastic was 2.9 N/mm2. Generally, conventional dental composite resin shows around 15 N/mm2 [24]. Therefore, the prepared PRX-based thermosetting plastic

ROMP-Derived cyclooctene-based monolithic polymeric materials reinforced with inorganic nanoparticles for applications in tissue engineering

• Franziska Weichelt,
• Solvig Lenz,
• Stefanie Tiede,
• Ingrid Reinhardt,
• Bernhard Frerich and
• Michael R. Buchmeiser

Beilstein J. Org. Chem. 2010, 6, 1199–1205, doi:10.3762/bjoc.6.137

• and CaCO3-reinforced monoliths) and 43 m2/g (HAp-reinforced monoliths). The microhardness of the monolithic materials was determined with a Vickers hardness measurement device. In comparison to the microhardness of unfilled COE-based monoliths (5.8 N/mm2), a more than 2-fold increase of the