Search results for "Polymer science"
showing 10 items of 157 documents
Interplay between Chain Collapse and Microphase Separation in Bottle-Brush Polymers with Two Types of Side Chains
2010
Conformations of a bottle-brush polymer with two types (A,B) of grafted side chains are studied by molecular dynamics simulations, using a coarse-grained bead−spring model with side chains of up to...
TI: Cyclophosphazenes as polymer modifiers
2003
The utilization of cyclophosphazenes as polymer modifiers is reviewed, with particular concern to their exploitation as versatile chain extenders, possibly for recycle problems, crosslinkers, to enhance mechanical properties of polymeric materials, branchers, to selectively introduce ramifications in linear polymers, and compatibilizers, to favor the formation of blends between originally incompatible organic macromolecules. The great versatility of the synthetic methods put forward for these substrates, together with the ease of controlling their modification, functionalization and reactivity are important parameters for the evaluation of which type of use is more feasible for these trimer…
Hermann Staudinger and the Future of Polymer Research Jubilees—Beloved Occasions for Cultural Piety
2004
1986
Preparation and mechanical characterization of fibres from a new copoly(ether-ester-amide) are reported. The mechanical characteristics are slightly lower than those of polyamide 6, but satisfactory for textile use, and the fibres have larger moisture absorption. This gives rise to more comfortable fibres preventing the accumulation of electrostatic charges. Die Herstellung und mechanische Charakterisierung von Fasern aus einem neuen Copoly(ether-ester-amid) werden beschrieben. Die mechanischen Eigenschaften sind etwas schlechter als die von Polyamid 6, aber ausreichend fur textile Anwendungen. Die Fasern weisen eine grosere Feuchtigkeitsabsorption auf. Dies fuhrt zu einem angenehmeren Verh…
Natural compounds as light stabilizer for a starch-based biodegradable polymer
2014
Abstract The photooxidation behavior of a commercial starch-based biodegradable polymer, i.e., new generation Mater-Bi, loaded with natural stabilizers was investigated in consideration for outdoor agricultural applications. The photooxidation behavior of the biodegradable films was monitored mainly by mechanical tests and spectroscopic analysis. In order to formulate biodegradable films without any synthetic compounds, suitable for outdoor applications and with good photooxidation stability, antioxidants such as α-tocopherol and quercetin (Q) were considered. The results obtained using natural compounds were compared with those obtained by using a synthetic antioxidant and a light stabiliz…
Absolutes Molekulargewicht der nativen Cellulose der Alge Valonia
1976
Der Polymerisationsgrad der nativen Cellulose der Alge Valonia wurde bei dem unfraktionierten Material zu Pw≈26500 und bei dem durch Fallungsfraktionierung isolierten hochmolekularen Anteil der Molekulargewichtsverteilung zu Pw≈44000 ermittelt. Diese letzte Grose legt die Dimension fest, die die synthetisierende Matrize geometrisch erfullen mus. Sie durfte um einen Faktor von ca. 3 groser sein als die bei der Baumwollcellulose mit Pw≈14000. In Verbindung mit anderen Untersuchungen wird eine Biosynthese des Cellulosemolekuls als sehr wahrscheinlich angesehen, die direkt auf einer flachenformigen Matrize zu einer gefalteten Kette fuhrt. Da die thermodynamisch kontrollierte Faltungslange zu me…
Influence of long chain branching on the elongational behaviour of different polyethylenes and their blends
1986
Elongational data on a series of polyethylenes with different structure and on their blends are presented in order to correlate the extensional behaviour with the long chain branching degree.