形状记忆树脂及其应用

形状记忆树脂是一种新型功能高分子材料．本文在论述其形状记忆原理的基础上，着重讨论了形状记忆树脂的种类、特性以及制各方法，并介绍了它们的应用与发展前景．     

聚合物形状记忆材料及其纤维、纳米复合体系的研究

本文回顾了形状记忆聚合物材料的理论研究。详细介绍了近年来形状记忆聚合物结构改性方面的研究情况，指出软硬段含量、交联度等对形状记忆材料的影响；同时介绍了纤维、纳米粒子改性形状记忆聚合物材料的研究状况，最后对聚合物形状记忆材料的前景并口应用，特别是医疗上的应用作了分析介绍。     

Ce-TZP材料形状记忆效应的研究

本文对相变增韧氧化锆陶瓷Ce-TZP材料的形状记忆效应进行了研究。研究结果表明:在张应力作用下,含有10mol％CeO_2的Ce-TZP陶瓷具有形状记忆效应。材料的形状记忆效应,由材料内稳定剂的含量及材料的显微结构所决定。记忆量与材料的变形量和环境的温度有关。本文还在理论上对产生形状记忆的条件及其机理作了初步分析和探讨。     

形状记忆材料在隔热阻燃防护服中的应用

形状记忆材料（SMMs）作为一种有应用前景的智能材料，在外界的机械、电、磁、光、热、酸碱度等多种刺激后发生记忆响应，近年来被应用到多种防护材料中。文章介绍了形状记忆高分子聚合物及复合形状记忆材料的形状记忆效应和作用机理，介绍了隔热阻燃防护服种类及其性能要求，论述了形状记忆材料在隔热阻燃防护服中的应用，并对形状记忆材料在隔热阻燃防护服应用中的不足与发展方向进行了展望。     

热敏形状记忆高分子材料及其应用

介绍了热敏形状记忆高分子材料及其应用。热敏形状记忆高分子材料是通过温度的变化实现形状的记忆与改变,利用其形状记忆功能,热敏形状记忆弹性体可应用在热缩管、油田封隔器、医用外科、保险杠等领域。     

智能型温敏形状记忆高分子材料的研究进展

综述了热致感应型形状记忆高分子材料的工作原理、形成记忆功能的方法及其分类和应用,介绍了热致感应型形状记忆纤维的生产技术和国内外研究发展状况,并对热致感应型形状记忆高分子材料的未来研究发展趋势作以评述。     

神奇的形状记忆材料

提起形状记忆材料 ,许多人一定感到很神秘 ,更多的人感到陌生。但是当您使用手机通话时 ,当您购买漂亮的文胸时 ;当您乘坐汽车外出旅游或出差享受豪华宾馆的住宿条件时 ,你也许就在同形状记忆材料打交道了。1　形状记忆材料的崛起形状记忆是指具有某一原始形状的制品 ,经过形变并定型后 ,在特定的外界条件下能自动恢复原始形状的现象。具有该现象的材料被称作形状记忆材料。形状记忆效应是 1 95 1年美国 Read等人在 Au-Cd合金中首先发现的 ,1 95 3年在 In- Ti合金中 ,也发现了同样现象 ,当时并没有引人注目。但是 ,1 964年美国 Buehler等…     

医疗固定用低软化点形状记忆聚合物的研究进展

分析了近年来国内外对医疗固定用低软化点聚合物材料结构与性能方面的研究情况，简述了形状记忆聚合物材料的形状记忆原理，介绍了医疗固定用低软化点聚合物的加工方法与性能等研究成果。并提出了目前该类聚合物材料作为医用固定材料存在的不足。     

形状记忆功能高分子材料的研究现状

讨论了形状记忆功能高分子材料的类型和特点,概述了反式聚戊二烯、交联聚乙烯、聚降冰片烯及聚氨酯等形状记忆功能高分子材料的实验和理论研究进展。重点介绍了反式聚异 一烯的结构、特性、形状记忆功能的原理、配方、性能及其应用领域与前景。     

纤维增强形状记忆复合材料及其应用

纤维增强形状记忆复合材料及其应用，它涉及一种形状记忆复合材料及其应用。本发明解决了目前形状记忆聚合物材料的刚度和强度等力学性能较差、变形回复时输出的外力较小、运动稳定性和可靠性较差的问题。本发明由形状记忆聚合物材料和纤维增强相材料组成。本发明各组分材料的体积分数为：形状记忆聚合物材料20％～95％，     

A novel supramolecular shape memory material based on partial α-CD-PEG inclusion complex

A novel supramolecular shape memory material was prepared based on partial α-CD-PEG inclusion complex, which contains α-CD-PEG inclusion crystallites as a fixing phase and naked PEG crystallites as a reversible phase. The recovery ratio of these materials could reach 97%. The characteristics of the material were investigated and a mechanism for the shape memory behavior was proposed.     

A novel type of shape memory polymer blend and the shape memory mechanism

A novel styrene-butadiene-styrene tri-block copolymer (SBS) and poly(?-caprolactone) (PCL) blend were introduced for its shape memory properties. Compared to the reported shape memory polymers (SMPs), this novel elastomer and switch polymer blend not only simplified the fabrication process but also offer a controllable approach for the study of mechanisms and the optimization of shape memory performances. Microstructures of this blend were characterized by differential scanning calorimetry (DSC), AFM microscope observation and tensile test. DSC results demonstrated the immiscibility between SBS and PCL. AFM images and stress-strain plot further confirmed the two-phase morphology within the blend. It was found that the SBS and PCL continuous phases contributed to the shape recovery and shape fixing performances, respectively. A detailed shape memory mechanism for this type of SMP system was then concluded and an optimized SMP system with both good recovery and fixing performances was designed from this mechanism.     

In-plane deformation of shape memory polymer sheets programmed using only scissors

This paper describes an unconventional, yet simple method to program sheets of shape memory polymer into a variety of two dimensional (2D) structures. The final shape is “encoded” by physically cutting an initial design out of a pre-strained film. The orientation of the initial cut-out relative to the direction of strain and the subsequent relaxation of strain via heating defines the final shape. The appeal of the approach described here is that an easy, low-cost cutting method can achieve a similar shape memory effect attained by more complex processing techniques. Unlike conventional methods, where the final shape of a shape memory polymer must be defined a priori, the direction of cutting of the polymer defines its final shape without any complex pre-programmed strain profiles. A geometric model relating the resolved 2D polymer shape to the initial shape and strain orientation reveals linear correlation between the model-predicted and experimentally-observed shapes. In addition to demonstrating the principle with simple rectangular shapes, we suggest geometries related to encryption and high aspect ratio fibers.     

Co-extruded multilayer shape memory materials: Nano-scale phenomena

Shape memory polymers (SMPs), which demonstrate the ability to possess multiple shapes, are traditionally produced from copolymers and recently from blends. These materials often have phase separated morphologies that possess domain sizes on either the nano- or micro-scale. The observed properties, specifically the shape memory behavior, can be significantly altered by a change in the domain size; however, doing this often requires modification to the materials or material production process. Forced assembly multilayer co-extrusion was used to produce shape memory materials with a continuous layered structure that can be easily tailored to cover layer thicknesses ranging from the nano- to the micro-scale. Upon decreasing the layer thickness of polyurethane/polycaprolactone (PU/PCL) layered films, improvement in the shape fixity and recovery ratios tracked with layer thickness. The improvement in properties was attributed to a change in the PCL crystal orientation from randomly oriented in microlayers to in-plane lamella orientation in nanolayers.     

Advances in Shape Memory Polyurethanes and Composites: A Review

Polyurethanes are synthetic smart materials having exquisite property to regain original shape from temporary shape when an external force (heat, light, electricity, and entropy driven deformation) is applied. Shape memory polyurethanes have ability to replace shape memory alloys due to cut-rate, easy manufacturing, programing, and high shape recovery ratio. The review focused on polyurethane types exhibiting shape memory effect and various categories of shape memory effects in polyurethane. Moreover, compound structure, modeling structure, applications, and related synthetic methods for shape memory polyurethanes are discussed. The strategies for induction of cross-linking and post cross-linking at high, medium, and low temperature are surveyed.     

Semi-crystalline two-way shape memory elastomer

Most shape memory polymers are rigid and exhibit only one way (irreversible) shape memory effect. This work explored the two-way (reversible) shape memory effect for semi-crystalline elastomeric networks. These semi-crystalline networks with various gel fractions and crosslinking densities were synthesized via radical initiated crosslinking of poly(ethylene-co-vinyl acetate). The thermal, mechanical, and the two-way shape memory properties of the resulting materials were investigated. The critical impact of the gel fraction on the two-way shape memory behaviors was revealed. The results from this study establish the basis for potential applications involving soft reversible actuation.     

Photopolymerized Thiol-Ene Systems as Shape Memory Polymers

In this study we introduce the use of thiol-ene photopolymers as shape memory polymer systems. The thiol-ene polymer networks are compared to a commonly utilized acrylic shape memory polymer and shown to have significantly improved properties for two different thiol-ene based polymer formulations. Using thermomechanical and mechanical analysis, we demonstrate that thiol-ene based shape memory polymer systems have comparable thermomechanical properties while also exhibiting a number of advantageous properties due to the thiol-ene polymerization mechanism which results in the formation of a homogeneous polymer network with low shrinkage stress and negligible oxygen inhibition. The resulting thiol-ene shape memory polymer systems are tough and flexible as compared to the acrylic counterparts. The polymers evaluated in this study were engineered to have a glass transition temperature between 30 and 40 °C, exhibited free strain recovery of greater than 96% and constrained stress recovery of 100%. The thiol-ene polymers exhibited excellent shape fixity and a rapid and distinct shape memory actuation response.     

New directions in the chemistry of shape memory polymers

The rapidly expanding field of shape memory polymers (SMPs) is driven by a growing number of potential applications, such as biomaterials, optics, and electronics. The basic concept involves polymers that can be trapped in a thermodynamically-unfavorable shape, then triggered by an external stimulus to return to their original shape, doing useful work in the process. Part of the attraction of using SMPs is that the energy released during actuation is stored in the polymer itself, rather than requiring an external force to change shape. This approach is beneficial for applications where external actuation is impossible or inconvenient. Polymers are also advantageous over shape memory metal alloys or ceramics in that there are endless combinations of functional groups and material properties to suit a variety of purposes, based on the monomers and polymerization conditions chosen. This advantage of SMPs is of particular interest in the development of materials with additional, desirable physicochemical attributes that are not necessarily coupled to the shape memory (SM) behavior itself. The SM behavior is quantitatively measured to facilitate comparison of various polymer systems, and researchers have used a number of defining parameters to guide the development and characterization of materials with extremely precise and reliable SM responses. In this review, recent trends in the structural or chemical characteristics of SMPs are explored, with an emphasis on how the molecular structure and functionality of each polymer affects its mechanical response.     

形状记忆聚氨酯的研究现状

从形状记忆聚氨酯的记忆机理、数学模型、形状记忆影响因素、以及近期实验和理论研究进展等方面介绍了形状记忆聚氨酯的研究现状。并对当前形状记忆聚氨酯的应用领域和发展趋势作了阐述。     

Shape memory behavior of poly(methyl methacrylate)-graft-poly(ethylene glycol) copolymers

This paper describes a shape memory behavior of graft copolymers poly(methyl methacrylate)-graft-poly(ethylene glycol) (PMMA-g-PEG). In shape memory test, the sample was deformed from its original shape to a temporary shape above glass transition temperature (T_g), cooled below T_g to fix the temporary shape, and subsequently heated above T_g for spontaneous recovery to the original shape. By grafting PEG onto PMMA backbone, shape memory ability was drastically enhanced than PMMA homopolymer. The shape recovery ratio was decreased with the increase in the shape deformation temperature. With considering a good miscibility of backbone and side chain in PMMA-g-PEG, this shape memory ability may be related to a physically cross-linked network structure by chain entanglement of the comb-like graft copolymer. Stress relaxation measurements were investigated in order to confirm the effect of the graft chains on the shape memory behavior.