Tuning the Mechanical Properties of Silkworm Silk Fibres by Thermally Induced Modification of Crystalline Nanostructure

Since copper has some advantages relative to aluminum as an interconnection material, it is appropriate to investigate its mechanical properties in order to be prepared in advance for possible problems, such as the cracks and voids that have plagued aluminum interconnect systems. A model previously used to interpret the behavior of aluminum films proves to be, with minor modification, also applicable to copper. Although the thermal expansion of copper is closer to that of silicon and, consequently, the thermally induced strains are smaller, the much larger elastic modulus of copper results in substantially higher stresses. This has implications for the interaction of copper lines with dielectrics.

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Thermally Induced Changes in the Chemical and Mechanical Properties of Epoxy Foam

Journal of Cellular Plastics ◽

10.1177/0021955x10381103 ◽

2010 ◽

Vol 46 (6) ◽

pp. 531-549 ◽

Cited By ~ 4

Author(s):

John M. Kinyanjui ◽

David W. Hatchett

Keyword(s):

Mechanical Properties ◽

Thermally Induced ◽

Epoxy Foam ◽

Induced Changes

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Development of Photocrosslinkable Urethane-Doped Polyester Elastomers for Soft Tissue Engineering

International Journal of Biomaterials Research and Engineering ◽

10.4018/ijbre.2011010102 ◽

2011 ◽

Vol 1 (1) ◽

pp. 18-31 ◽

Cited By ~ 10

Author(s):

Yi Zhang ◽

Richard T. Tran ◽

Dipendra Gyawali ◽

Jian Yang

Keyword(s):

Mechanical Properties ◽

Tissue Engineering ◽

Soft Tissue ◽

Hexamethylene Diisocyanate ◽

Elongation At Break ◽

Thermally Induced ◽

Molar Ratios ◽

3D Network ◽

Soft Tissue Engineering

Finding an ideal biomaterial with the proper mechanical properties and biocompatibility has been of intense focus in the field of soft tissue engineering. This paper reports on the synthesis and characterization of a novel crosslinked urethane-doped polyester elastomer (CUPOMC), which was synthesized by reacting a previously developed photocrosslinkable poly (octamethylene maleate citrate) (POMC) prepolymers (pre-POMC) with 1,6-hexamethylene diisocyanate (HDI) followed by thermo- or photo-crosslinking polymerization. The mechanical properties of the CUPOMCs can be tuned by controlling the molar ratios of pre-POMC monomers, and the ratio between the prepolymer and HDI. CUPOMCs can be crosslinked into a 3D network through polycondensation or free radical polymerization reactions. The tensile strength and elongation at break of CUPOMC synthesized under the known conditions range from 0.73±0.12MPa to 10.91±0.64MPa and from 72.91±9.09% to 300.41±21.99% respectively. Preliminary biocompatibility tests demonstrated that CUPOMCs support cell adhesion and proliferation. Unlike the pre-polymers of other crosslinked elastomers, CUPOMC pre-polymers possess great processability demonstrated by scaffold fabrication via a thermally induced phase separation method. The dual crosslinking methods for CUPOMC pre-polymers should enhance the versatile processability of the CUPOMC used in various conditions. Development of CUPOMC should expand the choices of available biodegradable elastomers for various biomedical applications such as soft tissue engineering.

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Stimuli-Responsive Nanodiamond–Polyelectrolyte Composite Films

Polymers ◽

10.3390/polym12030507 ◽

2020 ◽

Vol 12 (3) ◽

pp. 507 ◽

Cited By ~ 1

Author(s):

Tony Tiainen ◽

Marina Lobanova ◽

Erno Karjalainen ◽

Heikki Tenhu ◽

Sami Hietala

Keyword(s):

Mechanical Properties ◽

Phase Transition ◽

Composite Films ◽

Complexing Agent ◽

Mechanical And Thermal Properties ◽

Stimuli Responsive ◽

Phase Transition Behavior ◽

Thermally Induced ◽

Reversible Phase Transition ◽

Reversible Phase

Nanodiamonds (NDs) can considerably improve the mechanical and thermal properties of polymeric composites. However, the tendency of NDs to aggregate limits the potential of these non-toxic, mechanically- and chemically-robust nanofillers. In this work, tough, flexible, and stimuli-responsive polyelectrolyte films composed of cross-linked poly(butyl acrylate-co-dimethylaminoethyl methacrylate) (P(BA-co-DMAEMA)) were prepared by photopolymerization. The effects of the added carboxylate-functionalized NDs on their mechanical and stimuli-responsive properties were studied. When the negatively charged NDs were added to the polymerization media directly, the mechanical properties of the films changed only slightly, because of the uneven distribution of the aggregated NDs in the films. In order to disperse and distribute the NDs more evenly, a prepolymerized polycation block copolymer complexing agent was used during the photopolymerization process. This approach improved the mechanical properties of the films and enhanced their thermally-induced, reversible phase-transition behavior.

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