Highly Cross-Linked and Stable Shape-Memory Polyurethanes Containing a Planar Ring Chain Extender

2020 ◽  
Vol 2 (11) ◽  
pp. 5259-5268
Author(s):  
Qing Luo ◽  
Jing Chen ◽  
Pitchaimari Gnanasekar ◽  
Xiaozhen Ma ◽  
Dongdong Qin ◽  
...  
Keyword(s):  
Shape Memory ◽  
Chain Extender ◽  
Stable Shape

The Effect of Chain Extender Type on the Physical, Mechanical, and Shape Memory Properties of Poly(ε-Caprolactone)-based Polyurethane-ureas

2017 ◽  
Vol 56 (18) ◽  
pp. 1977-1985 ◽  
Author(s):  
Alireza Eyvazzadeh Kalajahi ◽  
Mostafa Rezaei ◽  
Farhang Abbasi ◽  
Gity Mir Mohamad Sadeghi
Keyword(s):  
Shape Memory ◽  
Chain Extender ◽  
Shape Memory Properties

scholarly journals Synthesis and properties of shape memory polyurethanes generated from schiff-base chain extender containing benzoyl and pyridyl rings

2018 ◽  
Vol 21 (1) ◽  
pp. 55-63 ◽  
Author(s):  
Neng-Chiao Weng ◽  
Chih-Fu Wu ◽  
Wen-Chin Tsen ◽  
Cheng-Lung Wu ◽  
Maw-Cherng Suen
Keyword(s):  
Schiff Base ◽  
Shape Memory ◽  
Chain Extender

Biodegradable shape memory polymers functionalized with anti-biofouling interpenetrating polymer networks

2016 ◽  
Vol 4 (32) ◽  
pp. 5394-5404 ◽  
Author(s):  
I. Dueramae ◽  
M. Nishida ◽  
T. Nakaji-Hirabayashi ◽  
K. Matsumura ◽  
H. Kitano
Keyword(s):  
Mechanical Properties ◽  
Shape Memory ◽  
Polymer Networks ◽  
Shape Memory Polymers ◽  
Chain Extender ◽  
Interpenetrating Polymer Networks ◽  
Hexamethylene Diisocyanate ◽  
Cross Linker ◽  
Copolymer Poly ◽  
Shape Memory Polyurethane

A novel type of shape memory polyurethane (SMPU) with high mechanical properties and biodegradability was constructed using a lactone copolymer (poly(ε-caprolactone-co-γ-butyrolactone), PCLBL), a diol- or triol-based chain extender (1,5-pentanediol, glycerol and 2-amino-2-hydroxymethyl-1,3-propanediol) and a diisocyanate cross-linker (1,6-hexamethylene diisocyanate).

Clay Reinforced Hyperbranched Polyurethane Nanocomposites Based on Palm Oil Polyol as Shape Memory Materials

2012 ◽  
Vol 548 ◽  
pp. 115-118 ◽  
Author(s):  
Ernie Suzana Ali ◽  
Syazana Ahmad Zubir ◽  
Ahmad Sahrim
Keyword(s):  
Shape Memory ◽  
Palm Oil ◽  
Chain Extender ◽  
Diphenylmethane Diisocyanate ◽  
Mixing Process ◽  
Clay Particles ◽  
Step Process ◽  
Hyperbranched Polyurethane ◽  
Shape Memory Properties ◽  
Polyurethane Nanocomposites

Reactive nanoclay reinforced hyperbranched polyurethane (HPU) nanocomposites have been synthesized with the introduction of palm oil polyol as part of the precursor. The HPU were prepared in a two-step process using polycaprolactonediol, 4,4’-diphenylmethane diisocyanate and 1,4-butanediol as chain extender. Nanoclay was added with the purpose of improving the properties of the pristine polyurethane. The introduction of palm oil polyol is believed to enhance the mixing process between polymer matrix and filler. Thermal, mechanical and shape memory properties of produced HPU were investigated. The results showed that the crystallinity of HPU nanocomposites decreased with introduction of clay particles and that the mechanical and shape memory properties were enhanced with the addition of small amount of reactive nanoclay (up to 3 wt%).

scholarly journals Effect of Nanofiller Dispersion on Morphology, Mechanical and Conducting Properties of Electroactive Shape Memory Poly(Urethane-Urea)/Functional Nanodiamond Composite

2015 ◽  
Vol 15 (4) ◽  
pp. 14-28 ◽  
Author(s):  
A. Kausar
Keyword(s):  
Electrical Conductivity ◽  
Tensile Strength ◽  
Shape Memory ◽  
Shape Recovery ◽  
Hard Segment ◽  
Soft Segment ◽  
Chain Extender ◽  
Solution Casting ◽  
Melt Blending ◽  
Solution Route

Abstract In this attempt, segmented poly(urethane urea) was prepared from polycaprolactone triol (soft segment), 1,3- bis(isocyanatomethyl)cyclohexane (hard segment) and 4,5-diaminophthalonitrile (chain extender). Acidfunctionalized nano-diamond was used as nano-filler. The nanocomposites were processed using solution casting and melt blending. Unique morphology was observed by SEM due to generation of crosslinked polyurethane and ND network. The s-PUU/ND 10 depicted 6 % increase in tensile strength compared with m-PUU/ND 10. 10 wt. % ND loading via solution route increased conductivity to 0.089 Scm-1 relative to m-PUU/ND 10 (0.057 Scm-1). Electrical conductivity of nanocomposites was enough to show electroactive shape recovery of 95 % (40 V).

Tensile Failure of 55-Nitinol Wire

1975 ◽  
Vol 33 ◽  
pp. 46-47
Author(s):  
F. I. Grace
Keyword(s):  
Shape Memory ◽  
Shape Memory Effect ◽  
Memory Effect ◽  
Stoichiometric Composition ◽  
Tensile Failure ◽  
Initial State ◽  
Initial Shape ◽  
Nitinol Wire ◽  
Cscl Type ◽  
Shear Transformation

An interest in NiTi alloys with near stoichiometric composition (55 NiTi) has intensified since they were found to exhibit a unique mechanical shape memory effect at the Naval Ordnance Laboratory some twelve years ago (thus refered to as NITINOL alloys). Since then, the microstructural mechanisms associated with the shape memory effect have been investigated and several interesting engineering applications have appeared.The shape memory effect implies that the alloy deformed from an initial shape will spontaneously return to that initial state upon heating. This behavior is reported to be related to a diffusionless shear transformation which takes place between similar but slightly different CsCl type structures.

Sign in / Sign up

Export Citation Format

Share Document