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51.
含氢聚甲基硅氧烷/聚丙烯酸酯复合乳液研究 Ⅰ.复合乳液的制备及其性能 总被引:1,自引:0,他引:1
合成了含氢聚甲基硅氧烷/聚(丙烯酸丁酯-羟甲基丙烯酰胺)复合聚合物乳液。探讨了引发剂用量、反应温度、聚合方法、含氢聚甲基硅氧烷及羟甲基丙烯酰胺含量对聚合反应转化率,聚合及存放稳定性的影响。考察了复合乳液的成膜性及胶膜性质。柔软性能测试表明,所制备的复合乳液可作为织物柔软剂使用。 相似文献
52.
D. Feldman 《Polymer》1983,24(3):359-364
In the present paper we shall deal with: (a) Polyblends made of a polyurethane (PU) based on a polyether and diphenyl-methane-diisocyanate and an acrylic terpolymer (AT) system and, (b) glass fibre reinforced poly-(organosiloxane), (SR). We now report some differential scanning calorimetry (d.s.c.) measurements and the effect of thermal cycling exposure on these polymers. Stress-strain tests were done on an Instron universal testing machine. The modification of the properties on the polymers after blending and reinforcing respectively are discussed. At certain ratio PU to AT the behaviour of the polyblend to thermal cycling exposure is better than that of PU. The presence of the reinforcing agent in the silicone polymer significantly improves its mechanical and thermal properties. 相似文献
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正交实验优选HTBN/聚氨酯合成的最佳工艺条件 总被引:1,自引:0,他引:1
以端羟基聚丁二烯-丙烯腈(HTBN)为软段、甲苯二异氰酸酯(TDI)为硬段和端氨基硅油为改性剂,合成了端氨基硅油改性HTBN型聚氨酯(PU)。以n(-NCO)∶n(HTBN)、n(硅油)∶n(HTBN)、n(扩链剂)∶n(HTBN)和硅油加入方式为主要影响因素,并以断裂伸长率、邵氏硬度、拉伸强度和定伸应力为考核指标,采用L9(34)正交实验方法优选该PU合成的最佳工艺条件。研究结果表明,当n(-NCO)∶n(HTBN)=1.6∶1、n(硅油)∶n(HTBN)=6∶100、n(扩链剂)∶n(HTBN)=5∶100且在后期加入端氨基硅油时,端氨基硅油改性HTBN型PU的综合性能最好。 相似文献
55.
以α,ω-二羟基聚甲基三氟丙基硅氧烷为基胶、烃基三乙酰氧基硅烷为交联剂、气相法二氧化硅为补强填料、氧化铁红为耐热添加剂、γ-(2,3环氧丙氧)丙基三甲氧基硅烷(KH 560)为增粘剂、二月桂酸二丁基锡为催化剂,制成脱酸型单组分室温硫化(RTV-1)氟硅密封剂。探讨了基胶黏度、气相法二氧化硅用量、交联剂结构及用量对密封剂工艺性能和力学性能的影响。确定的较佳配方为100份黏度19 000 mPa·s的基胶、15份甲基三乙酰氧基硅烷、20份气相法二氧化硅、5份氧化铁红、2份KH 560、1份二月桂酸二丁基锡。按此配方得到的脱酸型RTV-1氟硅密封剂的工艺性能、常温力学性能、耐高温性能、耐油性能达到或超过国外同类产品的水平。 相似文献
56.
Yuan Meng Weijing Xu Maureen R. Newman Danielle S. W. Benoit Mitchell Anthamatten 《Advanced functional materials》2019,29(38)
Polysiloxane elastomers represent a widely utilized soft material with excellent rubber‐like elasticity, biocompatibility, and biodurability; however, there is a lack of an effective and straightforward approach to manipulate the material's viscoelastic response. A facile hydrosilylation reaction is employed to integrate ureidopyrimidinone hydrogen‐bonding side‐groups into linear and crosslinked siloxane polymers to achieve biocompatible soft materials with a highly tunable viscoelastic relaxation timescale. Stacking of H‐bonded moieties is avoided in the designed macromolecular architectures with tight, side‐groups substituents. The obtained siloxane network features the presence of both covalent crosslinks and truly thermoreversible crosslinks, and can be formulated across a broad material design space including elastic solids, recoverable viscoelastic solids, and viscous liquids. The elastomers exhibit unique temperature‐dependent shape‐memory capability and show good cytocompatibility. Importantly, a deformed material's shape‐recovery occurs regardless of external triggering, and through manipulation of network formulations, the shape‐recovery timescale can be easily tuned from seconds to days, opening new possibilities for biomedical, healthcare, and soft material applications. 相似文献
57.
Flexible Hard Coating: Glass‐Like Wear Resistant,Yet Plastic‐Like Compliant,Transparent Protective Coating for Foldable Displays 下载免费PDF全文
Gwang‐Mun Choi Jungho Jin Dahye Shin Yun Hyeok Kim Ji‐Hoon Ko Hyeon‐Gyun Im Junho Jang Dongchan Jang Byeong‐Soo Bae 《Advanced materials (Deerfield Beach, Fla.)》2017,29(19)
A flexible hard coating for foldable displays is realized by the highly cross‐linked siloxane hybrid using structure–property relationships in organic–inorganic hybridization. Glass‐like wear resistance, plastic‐like flexibility, and highly elastic resilience are demonstrated together with outstanding optical transparency. It provides a framework for the application of siloxane hybrids in protective hard coatings with high scratch resistance and flexibility for foldable displays. 相似文献
58.
Jiayu Song Jie Liu Meng Li Shuai Li Michael Kappl Hans-Jürgen Butt Youmin Hou King Lun Yeung 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(37):2301561
Atmospheric water harvesting is considered a viable source of freshwater to alleviate water scarcity in an arid climate. Water condensation tends to be more efficient on superhydrophobic surfaces as the spontaneous coalescence-induced droplet jumping on superhydrophobic surfaces enables faster condensate removal. However, poor water nucleation on these surfaces leads to meager water harvest. A conventional approach to the problem is to fabricate micro- and nanoscale biphilic structures. Nonetheless, the process is complex, expensive, and difficult to scale. Here, the authors present an inexpensive and scalable method based on manipulating the water-repellent coatings of superhydrophobic surfaces. Flexible siloxane can facilitate water nucleation, while a branched structure promotes efficient droplet jumping. Moreover, ToF-SIMS analysis indicated that branched siloxane provides a better water-repellent coating coverage than linear siloxane and the siloxanes comprise hydrophilic and hydrophobic molecular segments. Thus, the as-prepared superhydrophobic surface, TiO2 nanorods coated with branched siloxanes harvested eight times more water than a typical fluoroalkylsilane (FAS)-coated surface under a low 30% relative humidity and performed better than most reported biphasic materials. 相似文献
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