共查询到19条相似文献,搜索用时 194 毫秒
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正工业化生产碳纤维按原料路线可分为聚丙烯腈(PAN)基碳纤维、沥青基碳纤维和粘胶基碳纤维三大类,其中由聚丙烯腈纤维原丝制得的高性能碳纤维,生产工艺较其他方法简单,产量约占全球碳纤维总产量的90%以上。 相似文献
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粘胶基碳纤维原丝的研制 总被引:1,自引:0,他引:1
在大量理论研究和调查的基础上,确定了粘胶基碳纤维原丝的技术指标,根据设备条件制定了合理的工艺路线,采取了一系列技术措施,研制成了均匀而优质的粘胶,为制造粘胶基碳纤维打下了基础. 相似文献
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对β-环糊精碱性条件下与环氧丙烷反应制备羟丙基-β-环糊精的工艺进行了优化。通过单因素试验确定了反应温度、反应时间和透析时间三个试验因素的取值范围,并用响应面分析法确定了最佳工艺参数:反应时间16.05h,反应温度31.06℃,透析时间7.41h。据此工艺参数制得羟丙基-β-环糊精的取代度达到4.10,得率61.80%。 相似文献
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Intended to study the influence of different production parameters on sound absorption of activated carbon fiber felts, viscose-based activated carbon fiber felts acquired from different production parameters were prepared and taken to test the sound absorption coefficients in normal incidence by means of transfer function method, within an acoustic range of 250–6300 Hz in the impedance tube. Analysis was made to find the influence of carbonization temperature, carbonization rate, activation temperature, and activation time on sound absorption properties. Sound absorption coefficients at medium–low frequencies strikingly climbed with the increasing frequency, while fluctuating at high frequencies. Other production parameters remaining constant, sound absorption coefficients increased at medium–low frequencies with the rising carbonization temperature and the extended activation time, while subsequently decreased with the rising carbonization rate and carbonization temperature. At the same time, sound absorption coefficients decreased at high frequencies with the rising carbonization temperature and carbonization rate, while increased but later decreased with the rising activation temperature, and increased again with the added time in activation. 相似文献
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为了建立活性炭纤维材料吸声性能预测模型,利用阻抗管对不同规格的粘胶基活性炭纤维材料在250-1600Hz中低频率声波范围内的吸声性能进行测试,根据Delany和Bazley提出的特性阻抗率和传播常数理论模型,采用最小二乘法建立了活性炭纤维材料声学特征参数特性阻抗率和传播常数预测模型。在此基础上,建立了活性炭纤维材料吸声系数模型,并对该模型计算结果和试验结果进行了比较,结果表明两者结果基本相一致,验证了建立的活性炭纤维材料吸声性能预测模型具有一定的可信度,为开发和设计活性炭纤维吸声材料提供理论依据。 相似文献
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The aim of this study is to explore the effects of different parameters on acoustic properties of activated carbon fiber felts. Seven viscose-based activated carbon fiber felts with different specifications were selected to test the sound absorption coefficients in normal incidence by using transfer-function method and an impedance tube in an acoustic range of 250–6300?Hz frequencies, and to analyze the effects on acoustic properties caused by factors such as: thickness, bulk density, and fiber diameter. The result demonstrated that activated carbon fiber felts exhibited exceptional acoustic properties. As frequency increases, sound absorption coefficients of less-thick felts went upwards in the whole range of frequencies; when the thickness amounted to 9?mm, sound absorption coefficients showed a sharp increase at low frequencies and a fluctuation at high frequencies. With the increase in thickness and bulk density, sound absorption properties improved first and then impaired at the same level of frequency; with a decrease in the fiber diameter, properties enhanced at the same level of frequency. When thickness and bulk density increased and fiber diameter decreased, sound absorption coefficients of the first resonance frequency displayed an upward trend to different degrees, while the first resonance frequencies declined discrepantly. 相似文献
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为制备具有较高孔隙率的聚丙烯腈(PAN)活性中空碳纳米纤维(AHCNF),以自行制备的PAN为原料,经同轴静电纺丝、预氧化、炭化、活化后制备得到AHCNF,借助X射线光电子能谱仪、扫描电子显微镜、比表面积测试仪研究了致孔剂对其形态与孔结构的影响。结果表明:制备的PAN共聚物环化温度较低,环化放热较缓和,有利于预氧化的进行;炭化过程将PAN表面的碳氧单键转化为碳氧双键,而活化过程将碳氧双键进一步转化为酯基;添加致孔剂和未添加致孔剂得到的PAN活性中空碳纳米纤维横截面呈明显的中空结构,纤维壁较为致密;添加致孔剂后,活性中空碳纳米纤维的总比表面积从55.719 m2/g增加到532.639 m2/g,孔容从0.070 cm3/g增加到0.312 cm3/g,介孔平均孔径从3.408 nm增加到4.309 nm,收率从27.14%降低到9.44%。 相似文献
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为给高性能碳纳米纤维的预氧化制备过程提供数据参考,通过多针静电纺的方法制备具有高取向的聚丙烯腈(PAN)纳米纤维束。通过研究纳米纤维结构,探讨了预氧化温度及时间对纳米纤维的结构和性能的影响。结果表明:整个纺丝过程可以持续5h以上,纳米纤维的直径在218nm左右,同时其沿纤维束轴向的取向度达到76.52%。纳米纤维的横截面成典型的外层致密内层松软的皮芯结构。随预氧化温度或者时间的增加,脱氢、环化以及氧化反应程度提高;随温度的提高,纳米纤维的结晶度先增加后减小,其最大结晶度达到54.57%。红外光谱、X射线衍射曲线以及芳构化指数表明:预氧化温度在260℃到280℃、时间1~2h之间较为合适。 相似文献
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