scholarly journals Advances in Elastomers

Materials ◽  
2021 ◽  
Vol 14 (2) ◽  
pp. 348
Author(s):  
Michal Sedlačík
Keyword(s):  
Consumer Goods ◽  
Medical Applications ◽  
High Elongation ◽  
Entropy Elasticity

Elastomer materials are characteristic for their high elongation and (entropy) elasticity, which makes them indispensable for widespread applications in various engineering areas, medical applications or consumer goods [...]

scholarly journals Soft, Formstable (Co)Polyester Blend Elastomers

Nanomaterials ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1472
Author(s):  
Axel T. Neffe ◽  
Victor Izraylit ◽  
Paul J. Hommes-Schattmann ◽  
Andreas Lendlein
Keyword(s):  
Crystallization Rate ◽  
Thermoplastic Elastomers ◽  
Sequence Length ◽  
Copolymer Composition ◽  
Medical Applications ◽  
Sequence Structure ◽  
Average Molar Mass ◽  
Elongation At Break ◽  
Polymer Systems ◽  
High Elongation

High crystallization rate and thermomechanical stability make polylactide stereocomplexes effective nanosized physical netpoints. Here, we address the need for soft, form-stable degradable elastomers for medical applications by designing such blends from (co)polyesters, whose mechanical properties are ruled by their nanodimensional architecture and which are applied as single components in implants. By careful controlling of the copolymer composition and sequence structure of poly[(L-lactide)-co-(ε-caprolactone)], it is possible to prepare hyperelastic polymer blends formed through stereocomplexation by adding poly(D-lactide) (PDLA). Low glass transition temperature Tg ≤ 0 °C of the mixed amorphous phase contributes to the low Young’s modulus E. The formation of stereocomplexes is shown in DSC by melting transitions Tm > 190 °C and in WAXS by distinct scattering maxima at 2θ = 12° and 21°. Tensile testing demonstrated that the blends are soft (E = 12–80 MPa) and show an excellent hyperelastic recovery Rrec = 66–85% while having high elongation at break εb up to >1000%. These properties of the blends are attained only when the copolymer has 56–62 wt% lactide content, a weight average molar mass >140 kg·mol−1, and number average lactide sequence length ≥4.8, while the blend is formed with a content of 5–10 wt% of PDLA. The devised strategy to identify a suitable copolymer for stereocomplexation and blend formation is transferable to further polymer systems and will support the development of thermoplastic elastomers suitable for medical applications.

SARI : A User-Oriented Data Bank System for Medical Applications

1976 ◽  
Vol 15 (02) ◽  
pp. 69-74
Author(s):  
M. Goldberg ◽  
B. Doyon
Keyword(s):  
Data Base ◽  
Personal Data ◽  
Data Bank ◽  
Medical Applications ◽  
Basic Principles ◽  
Base Management ◽  
General Data ◽  
Privacy Problem ◽  
Bank System ◽  
Made In

This paper describes a general data base management package, devoted to medical applications. SARI is a user-oriented system, able to take into account applications very different by their nature, structure, size, operating procedures and general objectives, without any specific programming. It can be used in conversational mode by users with no previous knowledge of computers, such as physicians or medical clerks.As medical data are often personal data, the privacy problem is emphasized and a satisfactory solution implemented in SARI.The basic principles of the data base and program organization are described ; specific efforts have been made in order to increase compactness and to make maintenance easy.Several medical applications are now operational with SARI. The next steps will mainly consist in the implementation of highly sophisticated functions.

Phase Model of Market Economy

2005 ◽  
pp. 41-47 ◽  
Author(s):  
N. Yegorenkov ◽  
E. Kazakova ◽  
M. Starodubtseva
Keyword(s):  
Market Economy ◽  
Consumer Goods ◽  
Imperfect Competition ◽  
Phase Model ◽  
Status Change ◽  
Means Of Production

The phase model of market economy is suggested in the article. It is formalized in the cubical equation The equation takes into account the imperfections of competition and the fact that consumer goods are produced with the help of means of production. Transitions from the imperfect competition to the perfect one and visa versa yield qualitative status change of market economy.

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