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1.
Composition and Properties of Thermo-regulated Non-woven Fabrics   总被引:1,自引:0,他引:1  
A series of non-woven fabrics were fabricated by blending S0- 80wt% of thennoregulated fibres containing n-elcosane, n-nonadecane or n-octadecane with 0 - 40wt% PET fibres and 0- 20wt% PP fibres. The phase change properties, thermal conductivity, thermal resistance, heat flux and inner temperature difference between wool felt and the thermoregulated non-woven fabrics of the non-woven fabrics were measured respectively. The thereto-regulated non-woven fabrics absorb heat at 25- 34℃ and release heat at 10- 25℃. The measured highest enthalpy of the non-woven is approximately 18J/g. During a heating process, heat flux of the non-woven fabrics is composed of three parts, heat absorbed by the cold textile touching the hot plate, heat transmitted from the hot plate to the cold plate, and the heat absorbed by PCM from the hot plate during the phase change process. The measured maximum inner temperature difference in a temperature rising process between the wool felt and the thermo-regulated non-woven fabric is approximately 8℃. The inner temperature difference (Tr-Ts〉0) lasts 16 - 45 min By contrary, the measured maximum inner temperature difference in the temperature decreasing process is approximately - 6. 5℃. The inner temperature difference (Tr-Ts〈0) lasts 16 - 50 min, The temperature regulation properties are obviously observed.  相似文献   

2.
运用低活性、柔性异弗尔二异氰酸酯与二乙烯三胺的界面聚合反应合成了以正十八烷为囊芯的聚脲微胶囊相变材料,并考察了乳化剂OP-10浓度和正十八烷浓度对微胶囊形成及形貌的影响。在优化的条件([OP-10]= 0.5%(质量分数),[正十八烷]=0.3 g/mL)下,制备了球形好、破损低、粒径均匀的微胶囊相变材料,并通过红外光谱、光学显微镜、气相色谱、热重分析等表征手段确定了微胶囊的化学结构、形貌及粒径、正十八烷的负载量和热稳定性。  相似文献   

3.
Magnetic microcapsules containing paraffin cores within urea-formaldehyde shells were fabricated utilizing in situ polymerization, with iron nano-particles as magnetic particles. The thermal properties, surface morphologies, magnetic properties and iron nano-particles content of the magnetic phasechange microcapsules were investigated by scanning electronic microscopy (SEM), differential scanning calorimetry (DSC), vibrating sample magnetometry (VSM) and inductively coupled plasma quantometry (ICP). The influence of iron nano-particles on morphologies was also considered. The results indicate that the melting point of magnetic phase-change microcapsules is almost identical to that of paraffin. The magnetism parameters such as specific saturation magnetization and residual magnetization of magnetic phase-change microcapsules increase with the increase of iron nano-particles content. Supported by National Natural Science Foundation of China (Grant No. 50436020)  相似文献   

4.
为优化马铃薯淀粉高吸水性树脂的合成工艺,采用水溶液聚合法进行接枝共聚制备高吸水性树脂,并对其性能进行研究.结果表明:当马铃薯淀粉与单体(g/mL)比例为1:7,丙烯酸与丙烯酰胺摩尔比为0.5:1,丙烯酸中和度为70%,反应温度60℃,引发剂、交联剂用量分别为单体的0.25 wt%,0.6 wt%,交联时间为1.5h.此条件下合成的高吸水性树脂吸蒸馏水倍率达到786 g/g,吸0.9% NaCl倍率达到76.1g/g,且吸水速率较快.对人工血、人工尿及一价阳离子溶液有较好的吸收率;热稳定性较好,保水能力强,在室温条件下保水能力在7d左右;在30、40、50、60℃条件下保水能力均优于科翰98保水剂,但耐酸性较差,在中性偏碱的条件下具有很好的吸水倍率.  相似文献   

5.
碳纳米管/铝基复合材料的制备与性能   总被引:1,自引:0,他引:1  
采用石蜡作为修饰剂分别对CNTs-COOH和纯Al粉进行修饰,物料经过粉碎、球磨、干压成型后,分别在650℃、670℃、690℃、720℃进行烧结,将烧成的坯体在500℃、30MPa压力下进行热压后挤出成型.分别采用硬度仪、万能试验机测试了样品的硬度及拉伸性能,利用扫描电镜观察烧结样品的断面形貌.结果表明:采用石蜡修饰后的CNTs,表现出较好的分散性;当复合材料的烧结温度为670℃时,制备得到CNTs(石蜡)/Al复合材料具有较高的硬度和较大的拉伸应力,复合材料呈现明显韧性断裂.  相似文献   

6.
Acryionitrilv-methyi mcthacrylate copolymer was synthesized in aqueous solution by Redox. The copolymer was mixed with 10 - 40 wt% of microencapsulated n-octadecane (MieroPCMs) in water. Copolymer films containing Mi- eroPCMs were cast at room temperature in N, N- imethyiformamide solution. The copolymer of acrylonitrile-methyl methacrylate and the copolymer films containing MicroPC- Ms were characterized by using Fourier Transform Infrared Spectroscopy (FTIR), Differential Scanning Calorimetry (DSC), Thermosravimetrlc Analyzer (TG), X-ray Diffraction (XRD) and Scanning Electron Microscopy (SEM), etc. The mierocapsules in the films are evenly distributed in the copolymer matrix. The heat-absorbing temperatures and heat-evolving temperatures of the films are almost the same as that of the MieroPCMs, respectively, and fluctuate in a slight range. In addition, the enthalpy efficiency of MieroPCMs rises with the contents of MicroPCMs increasing. The crystallirdty of the film increases with the contents of MicroPOMs increasing.  相似文献   

7.
Poly ( acrylonitrile-methyl acrylate) copolymer was synthesized by water depositing polymerization and has a typical feed ratio of 85/15. And then 1 - 3 wt% lauryl alcohol maleic anhydride (LAM) was adopted as stabilizer to mix with the acrylonitrile based copolymer. The mixtures were characterized by using Fourier Transform Infrared Spectroscopy (FTIR), Nuclear Magnetic Resonance (1 H NMR ), Gel Permeation Chromatography ( GPC ), Differential Scanning Calorimetry (DSC), optic microscope and Ubbelohde viscosimetryr etc. The melting point (Tm) and glass transition temperature (Tg) of the 85/15 AN/MA copolymer mixed with LAM all decrease with the increase of stabilizer content. The lowest Tg and Tm were 116.1℃ and 209. 1℃ respectively at the heating rate of 100℃/min when the content of LAM is 2 wt%. The 85/15 AN/MA copolymer mixed with 1 - 3 w t% LAM possess good thermal stability up to 30 min at 220 ℃.  相似文献   

8.
为了改善石蜡相变材料的封装效果和防火能力,利用不燃的酚醛树脂包裹石蜡制备出石蜡-酚醛复合胶囊,并利用石蜡-酚醛复合胶囊制备出水泥相变砂浆。实验结果显示,石蜡在常温范围内的相变热是20520 J·g-1,相变温度范围为27~38 ℃;石蜡-酚醛的相变热为4259 J·g-1,相变温度范围为18~30 ℃;相变砂浆的相变热为929 J·g-1,相变温度范围为20~29 ℃;相变砂浆的抗压强度、劈裂抗拉强度和粘结拉伸强度随着石蜡-酚醛胶囊掺量的增加而明显下降。工程应用表明,制备的相变砂浆在一定范围内具有较好的调节建筑室内温度,具有易存放、易施工、安全性高的特点  相似文献   

9.
采用乳液聚合法,以染料隐色体为芯材,交联聚(甲基丙烯酸甲酯-丙烯酸丁酯)(P(MMA-CO-BA))为壁材,通过调整BA在共聚单体中的质量分数制备了具有不同玻璃化温度的交联P(MMA-CO-BA)热敏型微胶囊.利用粒度分布仪、扫描电镜(SEM)、热重分析(TG)仪、差示扫描量热(DSC)仪表征了微胶囊的粒径分布、形貌、热稳定性和玻璃转化温度.结果表明:所得微胶囊具有良好的热稳定性;微胶囊粒子分布均匀,呈规则的球形;共聚单体中BA质量分数增加,微胶囊的平均粒径减小;BA在共聚单体中质量分数为5.0%,10.0%和15.0%时,所得微胶囊的玻璃化温度分别为115.0,110.3和94.3 ℃.  相似文献   

10.
以甲基丙烯酸正丁酯(BMA)为囊芯,密胺树脂为高分子囊壁材料,采用原位聚合法制备具有自修复功能的微胶囊.利用激光粒径分布仪、光学显微镜、微机差热天平和傅里叶变换红外光谱仪分别研究了微胶囊的粒径分布、表面形态、热性能和化学结构.讨论了乳化剂用量、搅拌速度以及芯材与壁材的投料质量比对微胶囊制备工艺的影响.结果表明:所得微胶...  相似文献   

11.
Phase change microcapsules(PCMs)are prepared with n-hexadecane and n-octadecane as core material,and melamine-formaldehyde resin is used as shell material by in-situ polymerization.Differential scanning calorimetry(DSC)was used to analyze the phase change properties.Thermal conductivity and maximum heat flux of cotton fabric finished with PCMs before and after being washed were also measured.It has been found that melting and crystal enthalpy of the PCMs decrease with decreasing the core/shell ratio,while q...  相似文献   

12.
以脲醛树脂为囊壁,氯化铵为固化剂,采用原位聚合法包覆了常温下为固体的石蜡,合成了相变储能微胶囊,运用偏光显微镜观察调酸过程中的微胶囊形成,傅里叶红外光谱仪分析微胶囊的化学结构,差示扫描量热仪研究微胶囊的储热性能,通过扫描电子显微镜表征微胶囊的表观形貌和微观状态.研究表明,该方法可有效包覆石蜡形成微胶囊,其形貌规则完整,...  相似文献   

13.
【目的】将前期分离到的1株具有高效植物促生作用和生物防治作用的解淀粉芽孢杆菌HZM9开发为可以进行田间应用的菌剂。【方法】首先以10种土传病害病原菌为指示菌,用生长速率法测定了HZM9菌株发酵液对各病菌的抑制作用; 又以榉树枯萎尖孢镰刀菌(Fusarium oxysporum)为指示菌,测定了发酵液在不同条件下的稳定性。【结果】供试的10种土传病害病原菌经菌株HZM9发酵液处理后,菌丝生长均受到明显的抑制,特别是对尖孢镰刀菌和大豆菌核(Sclerotinia sclerotiorum)的抑菌率均达90%左右。菌株HZM9发酵液有很好的热稳定性,温度升至80 ℃后其抑菌作用变化十分微弱,抑菌率仍然保持在80%以上; 100 ℃处理30 min抑菌率会下降到66.55%,100 ℃处理120 min,抑菌率仍能达到58.78%; 在普通光照和紫外线照射后可以保持稳定的抑菌活性,在pH 5~9和蛋白酶的处理后抗菌活性也很稳定; 在4 ℃下可以持续储藏150 d。【结论】HZM9具有广谱抑菌活性和很好的稳定性,能够适用于土传病害的生物防治。  相似文献   

14.
饱和一元脂肪醇类相变材料的蓄热特性   总被引:3,自引:0,他引:3  
以探索饱和一元脂肪醇作相变蓄热材料的可能性为目的,文中选择十八醇进行了量热学的实验研究。基于提出的凝固点和过冷度研究方法,由试验测得十八醇的凝固点为57.12℃ ,过冷度为0.01℃。十八醇的相变热为242.85J/g。另外,经50次冷热循环,十八醇凝固点与相变热的偏差分别为0.26 %和0.18%。上述结果表明十八醇为相变热大、过冷度小、热稳定性良好的相变材料.  相似文献   

15.
采用芯材为石蜡,壁材为密胺树脂,相变温度为35.66℃,相变潜热为158.7J/g的微胶囊相变材料制备制冷背心原理样衣,与隔绝式防护服配套使用,并委托中国人民解放军北京防化研究院生理评价试验中心对制冷背心进行生理评价试验。在室温36℃,相对湿度60%的条件下,测定穿着隔绝式防护服配有制冷背心前后的人体胸温、手温、腿温和肛温等参数随穿着时间的变化关系;结合人体产热,散热经验式与伍德科克人体散热理论建立模型,探讨人体穿着隔绝式防护服配有制冷背心前后人体平均体温随穿着时间的变化关系,并对如何提高人体着装舒适度和延长隔绝式防护服穿着生理时限进行综合分析。结果表明:穿着隔绝式防护服配有制冷背心前后,人体胸温、背温、手温、腿温和肛温明显下降;通过建模计算分析,穿着隔绝式防护服配有制冷背心前后的人体平均体温随穿着时间的变化关系计算值与实验测试结果吻合,变化趋势一致;在相同条件下,穿着配有制冷背心的隔绝式防护服过程中,人体体温较穿着未配有制冷背心的隔绝式防护服有所下降,上升幅度较小。  相似文献   

16.
低碳海洋平台用钢E40-Z35的研制   总被引:2,自引:0,他引:2  
通过实验室热模拟实验确定工艺参数,开发了连铸坯生产海洋平台用钢E40-Z35的控轧控冷工艺,并进行了现场工业试制.结果表明:采取低碳(w(C)≈0.08%)微合金化成分设计,利用Ca球化处理MnS夹杂物,以及轧制过程中进行高温慢速大压下,未再结晶区开轧温度为900℃,终轧温度为800℃,终冷温度为640℃左右.热轧后产品的-40℃常规冲击和时效冲击吸收功高于200J,厚度方向断面收缩率高于45%,具有良好的抗层状撕裂性能,满足船级社对海洋平台用钢E40-Z35的要求.  相似文献   

17.
为了给石蜡性能改进和应用提供科学依据,采用数字熔点仪﹑材料万能试验机等,在硬脂酸质量分数为0~100% 范围内,研究了石蜡-硬脂酸混熔体系的熔点和抗压强度特征,并采用红外吸收光谱对其机理进行分析,研究结果表明:硬脂酸对石蜡熔点有一定影响,当其质量分数在0~40%范围内,其熔点呈缓慢降低趋势,其后逐渐升高;硬脂酸对石蜡强度有明显的增强作用,尤其是质量分数在0~10%范围内,石蜡强度迅速升高,强度增长率达32.56%,其原因主要与硬脂酸能够去除石蜡中的气泡、提高石蜡均匀性有关;根据红外吸收光谱测试结果,石蜡与硬脂酸在组成上存在诸多相似之处,所以二者可按任意比例实现物理相熔;在工业应用中,若要提高石蜡的强度,而又不明显降低其熔点,硬脂酸质量分数应小于20%。  相似文献   

18.
Membranes formed by polysulfonamide (PSA) and phosphotungstic acid (PWA) supported on nano-silica have been prepared. Fourier transform infrared spectra (FTTR) and thermogravimctric analysis (TGA) were used to characterize the structure and thermal properties of obtained membranes. The analyses of water uptake, proton conductivity and mechanical properties of the membranes revealed that PWA and silica produced a beneficial effect on proton conduction of the membranes. The membranes with 50 wt% of PWA-SiQ2/PSA were mechanically stable and gave proton conductivity of 2. 57 × 10-2 S ?cm-1 at 90℃and 100% relative humidity. According to the obtained results, PWA and SiO2 doped PSA is a promising material for proton exchange membrane.  相似文献   

19.
尖晶石-氧化锆复合材料的制备与性能   总被引:1,自引:0,他引:1  
以高纯镁砂、煅烧Al2O3、稳定氧化锆为原料,以2%的TiO2为烧结添加剂,试样经100 MPa压力成形后,在1600℃3 h下烧成,制备出尖晶石-氧化锆复合材料。研究了氧化锆及氧化钛烧结添加剂对复合材料烧结性能、抗热震性能等的影响。试验研究结果表明:在MA尖晶石配料中引入10%的ZrO2,MAZ试样的抗热震性能优于MA尖晶石试样。引入TiO22%的MAZ-T复合材料试样结构致密,晶粒间为直接结合状态,体积密度达3.42g.cm-3,抗折强度为48.54 MPa,抗热震性能提高,该MAZ-T复合材料有希望用作水泥回转窑烧成带耐火材料。  相似文献   

20.
将竹材在200-400℃无氧环境中热处理3 h,然后对热处理竹材进行苯甲基化改性,探讨了反应时间、NaOH用量、相转移催化剂用量对醚化反应的影响.通过反应后热处理竹材的增重率来表征醚化反应程度,在同样的反应条件下,250℃热处理竹材的增重率最大,并通过FT-IR、XRD对苯甲基产品的微观结构进行了表征.  相似文献   

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