Self-Healing Polyurethane Elastomer Based on Crosslinked-Linear Interpenetrating Structure: Preparation,Properties, and Applications

Despite tremendous advances in the preparation of self-healing flexible strain sensor devices, it remains a great challenge to large-area synthesis, relatively high mechanical strength, and sensitive sensing properties into one self-healing materials system, which have received increasing interests because of their many potential applications. Herein, the design and synthesis of a crosslinked-linear interpenetrating structure polymer containing disulfide and hydrogen bonds is reported to address this conundrum. The resulting self-healable polymer is highly stretchable (up to 551.7%) with a high tensile strength (4.14 MPa) and excellent healing efficiency of similar to 90% at mild temperature without using any external reagents. Furthermore, a novel method for fabricating flexible sensor is also proposed to endow the resulted sensor with large-area (20 cm × 12 cm), low cost, and outstanding sensitivity to strain, which makes it very suitable for human motion monitoring applications. This work will provide afflatus on future design, fabrication, and application of self-healing flexible strain sensor devices.     

含DA键自修复硅氧烷环氧树脂性能研究

将环氧氯丙烷与糠醇反应,合成糠基缩水甘油醚(FGE),再用含双烯体结构的糠胺,将环氧双封头两端连接FGE,得到端基为四元呋喃结构的中间体,与含亲双烯体结构的1,6–双马来酰亚胺基己烷(1,6–BMI)进行交联固化,得到含有Diels-Alder(DA)键的自修复硅氧烷环氧树脂(EP–DA).通过红外分析仪、差示扫描量热...     

Interpenetrating Polymer Networks of Hydrocarbon and Fluorocarbon Polymers: Epoxy/Fluorinated Acrylic Macromonomers

A fluorinated acrylic resin was synthesized for use as a co‐monomer with a commercially available epoxy resin for UV‐cured interpenetrating polymer network preparation. Hybrid IPN networks were achieved with morphology ranging from a co‐continuous IPN to complete phase separation simply by changing monomer ratios. Highly hydrophobic coatings with good adhesion properties on glass substrates were obtained.

     

增韧改性环氧树脂互穿网络聚合物的合成与表征

合成了端异氰酸酯/环氧丙烯酸树脂互穿网络聚合物,在环氧树脂交联网络中引入柔性链段,达到增韧的目的。通过改变端异氰酸酯和环氧丙烯酸树脂的组分比,合成不同组成的互穿网络聚合物(IPNs)。借助红外光谱和扫描电镜等分析方法,研究了IPNs的分子混合形态结构。同时采用差热分析法(DSC)测试了聚合物的玻璃化转变温度,结果表明:端异氰酸酯预聚体含量越高,聚合物的玻璃化转变温度越低。对成膜物的力学性能研究表明,INPs的拉伸强度在端异氰酸酯/环氧丙烯酸树脂比例为30:70时,拉伸强度为55.24 MPa,是纯环氧树脂的2.5倍。     

UV‐Cured Interpenetrating Acrylic‐Epoxy Polymer Networks: Preparation and Characterization

Acrylic‐epoxy interpenetrating polymer networks were prepared by means of UV curing. The photopolymerization process was investigated via real‐time FTIR spectroscopy. The hybrid, cured films showed a broad tan δ peak in DMTA demonstrating the high damping properties of the hybrid, cured formulations. A decrease on shrinkage was achieved by increasing the epoxy‐resin content in the photocurable formulation, with a consequent increase in adhesion properties.

     

Synthesis and Properties of Interpenetrating Polymer Networks Composed of Epoxy Resins and Polysulphones with Cross-linkable Pendant Vinylbenzyl Groups

Polysulphones with cross-linkable pendant vinylbenzyl groups (PSF-VB) were prepared via chloromethylation of commercial polysulphones. The curing reactivity of PSF-VB was investigated by differential scanning calori-metry. Interpenetrating polymer networks (IPNs) were prepared based on bisphenol A diglycidyl ether (DGEBA) and PSF-VB, where DGEBA was cured by 4,4′-diaminodiphenyl sulphone and VB groups of PSF-VB were radically polymerized using dicumyl peroxide (DCP). Polysulphones having pendant benzyl groups (PSF-Bz) were also prepared and used as non-reactive modifiers. The fracture toughness (K_IC) for the resulting epoxy/PSF-VB IPN increased by 65% with no loss of mechanical properties on 10wt% addition of PSF-VB (7·9mol% VB unit, MW 74000). Non-reactive PSF-Bz was less effective than PSF-VB. Although the PSF-Bz modified resin had a particulate structure, the morphologies of the PSF-VB/epoxy IPNs were not clear from scanning electron micrographs. Furthermore, the epoxy/PSF-VB IPNs had higher solvent resistance than the epoxy/PSF-Bz blends. Morphological behaviour, modification results and high solvent resistance of the cured epoxy/PSF-VB resins indicate that cross-linked PSF-VB and the epoxy network entangled fully in the presence of DCP. © of SCI.     

互穿网络聚合物的研究进展

互穿网络聚合物(IPN)是一种新型复合物材料,文章介绍了IPN原理与几种表征手段,探讨了IPN在乳液涂料工艺中推广应用的前景。     

互穿网络结构复合材料中网络陶瓷预制体的制备与研究进展

介绍了网络陶瓷预制体的制备方法及研究进展,分析了各种制备方法的特点。总结了网络陶瓷预制体的优缺点,并对制备工艺发展方向作出展望。     

以HTPB为基的聚氨酯(PU)/聚甲基丙烯酸I酯互穿聚合物网络的研究

通过在以端羟基聚丁二烯(HTPB)为基的聚氨酯(PU)中引入聚甲基丙烯酸Ⅰ酯(PIMA)合成了一种新型互穿聚合物网络(IPN)，傅立叶红外光谱显示两相基本反应完全。静态力学拉伸测试表明，加入PIMA能显著改善IPN的力学性能，并用TEM对其微观形态进行了观察，发现两相互穿均匀，并显示出较好的相容性。     

聚甲基乙烯基硅氧烷／聚丙烯酸丁酯顺序互穿聚合物的性能研究

采用将聚甲基乙烯基硅氧烷（孙爪幅）在丙烯酸丁酯单体（BA）与引发剂过氧化苯甲酰组成的溶液中溶胀一定时间后，BA在PMVS中原位聚合的方法，制备出PMVS／聚丙烯酸丁酯（PBA）顺序互穿聚合物（PMVS／PBASIPNs），利用红外光谱、动态力学分析和热失重分析研究了材料表面与内部的分子结构、动态力学性能和热分解性能。结果表明，PBA的浓度在复合体系厚度方向上呈梯度分布，其浓度从表面向内部依次增加。与PMVS相比，PMVS／PBASIPNs阻尼性能较好，其损耗因子tanδ最大值为0．63，tanδ大于0．3的温度范围为-41～-9℃。根据不同升温速率下的热重分析曲线，用Doyle方法得到在分解率α=0．1～0．5时，热分解反应级数为一级反应，反应活化能E为143．4kJ·mol^-1。     

蓖麻油聚氨酯互穿网络型聚合物性能的研究

分别用甲苯二异氰酸酯(TDI)和六亚甲基二异氰酸酯(HDI)与蓖麻油(CO)反应制备出两种聚氨酯预聚体,再用预聚体与苯乙烯、丙烯腈、甲基丙烯酸甲酯、环氧树脂(E-44或E-51)等单体制备出蓖麻油聚氨酯互穿网络型聚合物(CO-PU IPN),研究了体系组成对该聚合物拉伸强度的影响。结果表明,随着固化时间的延长,CO-PU IPN的拉伸强度逐渐增大,TDI型CO-PU IPN比HDI型的拉伸强度大;烯类单体比环氧树脂单体所制CO-PU IPN的拉伸强度大,不同烯类单体之间的差别不大;增加预聚体中NCO/OH的摩尔比,CO-PU IPN的拉伸强度都是先增加,后减小,在摩尔比为2.25时出现最大值;添加抗氧剂1010、紫外光吸收剂UV-327和光稳定剂292等对CO-PUIPN的拉伸强度基本没有影响。     

不饱和聚酯与聚丙烯酸酯互穿网络聚合物的合成与表征

运用连续滴加单体法合成了聚羟基丙烯酸酯预聚体,运用多次投料法合成了不饱和聚酯,分别用环氧树脂和邻苯二甲酸酐、苯乙烯做固化剂制得不饱和聚酯与聚丙烯酸酯互穿网络聚合物;通过傅立叶变换红外光谱仪(FTIR)、凝胶渗透色谱仪(GPC)、热失重分析仪(TG)、示差扫描量热分析仪(DSC)、扫描电镜(SEM)等对聚合物的结构特征、分子量大小及其分布、热稳定性、玻璃化转变温度、表面形态等进行了研究。     

复合互穿聚合物网络涂料的制备和性能研究

用环氧树脂（EP）、氨基树脂（AR）、改性醇酸树脂（AK）、二官能度低聚物（BFO）和甲苯二异氰酸酯（TDI）等为原料,制备出了EP/TDI、AR/TDI、AK/TDI、BFO/TDI等4种物质相互贯穿、相互缠绕的高抗冲击性的聚合物涂膜,研究了本聚合物（IPN）涂膜组分的不同比例在硬度升高时的抗冲击性能,并应用DSC和SEM对IPN的互穿相及断裂口进行了分析。     

Self-Healable and Transparent Elastomers Based on Dual Reversible Networks

The fabrication of silicon elastomer with good mechanical properties and self-healing ability is still a challenge. Herein, a facile method to fabricate a transparent healable double-network (DN) elastomer by introducing polyborosiloxane (PBS) into self-healing polydimethylsiloxane (HPDMS) networks is demonstrated. Tensile testing shows that the mechanical properties of PBS and HPDMS are both improved. The DN elastomer shows high transparency across the visible spectrum with an average transmittance of 75%. Because of the breakage and reconstruction of reversible imine bonds and B O dative bonds, the elastomer exhibits excellent self-healing properties with a maximum healing efficiency of 98% at room temperature. Meanwhile, the elastomer can be repeatedly reprocessed with a recovery of 85% of virgin mechanical strengths. This work provides a new insight to design transparent, self-healing silicone elastomers with a simple and eco-friendly method.     

聚天冬氨酸/聚丙烯酸互穿网络吸水性树脂的制备

以交联聚天冬氨酸(PAsp)、丙烯酸(AAc)为原料,以过硫酸钾为引发剂,以N,N′-亚甲基双丙烯酰胺为交联剂,采用分步法制备了聚天冬氨酸/聚丙烯酸(PAAc)互穿网络吸水性树脂(IPNAP),并对其结构进行了表征,探讨了AAc与PAsp质量比、引发剂用量(以单体质量计,下同)、交联剂用量(以单体质量计,下同)、AAc中和度对IPNAP吸液性能的影响。结果表明,当AAc与PAsp质量比为1.0∶1、引发剂用量为0.50%、交联剂用量为0.40%、AAc中和度为75%时,IPNAP的吸液性能最好,在蒸馏水和生理盐水中的吸液倍率分别达到826g·g-1和120g·g-1。     

Synthesis and Characterization of Interpenetrating Biopolyester Networks Using Naturally Available Renewable Resources

Biodegradable crosslinked biopolyesters and interpenetrating networks (IPN) were prepared with poly(cardanol fumarate) (MCFR) and poly(castor oil fumarate) (CFR). In addition, polymerization and crosslinking with styrene-free vinyl monomers, vinyl acetate (VA), and n-vinyl pyrrolidone (VP) were adopted to prepare these materials. The IPNs have higher thermal stability and mechanical properties in comparison with the crosslinked biopolyesters. The improved characteristics of IPNs are due to the synergistic effect of physical and chemical crosslinking. These IPNs undergo gradual degradation in various media in comparison with crosslinked biopolyesters.     

Interpenetrating Polymer Networks Based on Gelatin and Poly(Vinyl Pyrollidone): Evaluation of Degradation,Histocompatibility, Cytotoxicity,and Drug Release

Interpenetrating polymer networks (IPNs) based on crosslinked gelatin [Gx] and poly(vinyl pyrrolidone) [PVPx] were synthesized using gamma irradiation. Degradability of IPNs was found to be dependent on the irradiation dose and crosslinker concentration as well as on the composition of IPNs. Samples prepared at dose of 0.07 and 0.14 Mrad degraded within 15 days in comparison to samples prepared at higher doses [0.20, 0.25 Mrad, and 0.30 Mrad]. Cell viability and histocompatibility studies suggest that IPNs based on gelatin and PVPx can be used as biodegradable drug delivery devices.     

Dynamic Polyphosphazene Networks with Modulating Shape Memory and Self-Healing Capacity by Double Coordination Interactions

A modern class of self-healing polyphosphazene elastomers has been synthesized using coordination bonds for the first time. Two categories of carboxyl-modified polyphosphazene have been synthesized, and 16 cross-linked polymers have been fabricated by tuning the concentration of different metal ions, which also allows modifying the properties of the elastomer by adjusting the interactions. This design enables the polymer network to form a hierarchical and dynamic structure without introducing complex ligands. The polyphosphazene networks can be toughened and enhanced by the dynamic coordination structure. Due to the distinct design, the synthesized elastomers show unprecedented properties in halogen-free polyphosphazenes, including high tensile stress (1.82 MPa), high malleability (≈1100%), shape memory, self-healing, and thermal processing capacity.     

不饱和聚酯／聚氨酯互穿网络聚合物的力学性能和形态结构的表征

对由不饱和聚酯和聚氨酯形成的不同组成的互穿网络聚合物的缺口冲击强度,拉伸强度及弯曲强度等力学性能进行了分析,并由透射电子显微镜观察了这种材料的形态结构,结果表明,当聚氨酯用量为１０％～２０％（质量分数）时,聚合物形成较好的互穿网络结构,使材料具有较高的冲击强度及拉伸强度,但对弯曲强度影响不大。