己内酰胺聚合管V型挡板的研制

在己内酰胺直型聚合管设计中采用了 V型挡板 ,经模拟试验和实际应用 ,效果均十分明显。采用 V型挡板改善聚己内酰胺熔体的径向混合效果 ,有效地减少己内酰胺熔体的径向温差 ,确保聚合物相对分子质量的稳定     

用VC062型聚合管生产尼龙6高粘切片

用VC062型聚合管生产纺制帘子线用尼龙6高粘切片。对设备及工艺进行了改造,提高进料管的物料温度,提高物料在前聚合器的开环速率,增加排水措施,促进VK管中产物分子量的提高。     

己内酰胺聚合反应工程CAD软件包——Ⅰ.工业化生产实际值与软件包计算结果的比较

介绍了己内酰胺聚合反应工程 CAD软件包的建立 ,用工厂单 VK管聚合和两步法聚合生产工艺验证了该软件包的可靠性。通过计算可得到单体转化率、聚合物聚合度、相对粘度、相对分子质量分布、环状二聚体含量、反应潜热等重要参数在聚合管中的变化情况     

聚酰胺纤维

20021064聚酞胺6生产技术和聚合物改性的持续发展Bergman K.;Chemleal Fibers International .2000,50,(6).p,536(英)尼龙6制造技术包括聚合物连续式和间歇式生产技术和高性能尼龙6的生产都适合运用高速纺。一步法聚合使用VK管,它由下部的柱塞流区和上部的混合伏组成。己内酞胺在进入VK管前受到由推流区回收的能量的预热。两步法聚合是在VK管聚合前,使用在仄力下高水份的预聚合。高性能尼龙6特点是改善J”挤出能力的熔化物、热学、化学、服用性的稳定,这是由一J:加入了作为链稳定剂的三二梭酸和改善染色性能的的酸胺添加剂。(姚慧婉)…     

Ф1000VK管加压聚合改造简介

江苏群发化工有限公司于 2 0 0 2年对己内酰胺聚合装置 2 #  1 0 0 0前聚合器进行了加压聚合改造 ,改造后装置的生产能力得到较大提高 ,产品质量得到改善。1 1 0 0 0VK管加压聚合的主要工艺参数　　加压聚合改造后的主要工艺参数见表 1。表 1　主要工艺参数项目参数项目参数预热器温度 /℃ 160熔体温度 /℃前聚压力 /MPa 0 .2　前聚 (上 ) 2 5 5后聚真空度 /MPa 0 .0 45　前聚 (下 ) 2 77聚合反应器产能 /t·d- 1 19.5　后聚 (上 ) 2 70前聚停留时间 /h 3 .10　后聚 (中 ) 2 72后聚停留时间 /h 16.10　后聚 (下 ) 2 5 22　加压聚合改…     

乙烯气相聚合工艺参数优化及反应过程的数学模型建立北大核心

利用典型的限制几何构型催化剂催化乙烯与1-丁烯或1-己烯的共聚合,研究了聚合温度、共聚单体含量以及氢气用量对催化剂活性、聚乙烯熔体流动速率和密度的影响。结果表明:随着聚合温度升高,催化剂活性先升高后降低;聚合温度的提高、共聚单体含量及氢气用量的增加均会导致聚乙烯的熔体流动速率升高;随着共聚单体含量的增加,所制聚乙烯的密度逐渐降低。另外,建立了乙烯聚合过程的数学模型,并利用数学模型指导了乙烯聚合过程的研究和质量控制。     

乙烯气相聚合工艺参数优化及反应过程的数学模型建立

利用典型的限制几何构型催化剂催化乙烯与1-丁烯或1-己烯的共聚合,研究了聚合温度、共聚单体含量以及氢气用量对催化剂活性、聚乙烯熔体流动速率和密度的影响。结果表明:随着聚合温度升高,催化剂活性先升高后降低;聚合温度的提高、共聚单体含量及氢气用量的增加均会导致聚乙烯的熔体流动速率升高;随着共聚单体含量的增加,所制聚乙烯的密度逐渐降低。另外,建立了乙烯聚合过程的数学模型,并利用数学模型指导了乙烯聚合过程的研究和质量控制。     

工艺及设备

20031230PA6生产的新成本效益Stibal W.;Chemieal Fibers International Man一MadeF iber Year Book,2001,p.sl(英)Ems xnventa一Fischer建造日产130吨尼龙6一步法聚合物生产装置和日产250吨两步法聚合物生产装置。生产工艺包括:聚合、蒸馏、进料、再聚合,蒸发、萃取和干燥。浓缩萃取水再聚合在VK管于大气压力下进行以减少环状二聚物浓度。将环状二聚物浓度降至热力学平衡水平是可能的,但温度和时间必须与其相适应。改进后的VK管可将环状二聚物浓度降至1.2%。标准VK管的环状二聚物浓度为2.2%。用再聚合原料生产的尼龙6产品质量与那…     

国内外直型 VK 管的差距

对国内外一部分尼龙6厂家使用的直型 VK 管进行了实地考察和对比,认为国产直型 VK 管处于落后状态:设备结构过于简单,生产能力小,所生产的产品质量较差。爱姆斯—伊文达公司设计的直型 VK 管比较先进,设计合理,在技术上处于领先地位。针对国产直型 VK 管存在的缺陷,建议有关研究设计院研制具有中国特色的直型 VK 管,以利于发展我国的尼龙生产。     

锦纶6水解连续聚合工艺及设备的改进

我厂广大职工为进一步实现“优质、高产、低耗”以及赶超国际先进水平的目标,遵照伟大领袖毛主席“洋为中用”的教导,并吸收国内各兄弟厂的先进经验,将常压聚合管中原孔板式挡板改为伞形的换向器,促使聚合体在聚合管中产生中心和管壁的对流,达到缩小径向温差,提高聚合体的内在质量,挖掘单机生产潜力。并同上海纺织工学院共同研究摸索出合理的工艺条件,初步得到了一些效果。     

Polyamide-6 polymerization and its melt flow in the VK tube reactor with optimized baffle structure

The flow mechanism of Polyamide-6 (PA6) melt over conical perforated baffles in the VK tube is elucidated by computerized analysis based on a rational assumption of Stokes' flow. The governing equations for a two-dimensional flow are solved by the finite difference method to generate the stream function profile, velocity field and residence time distribution. Optimization of the geometries of the baffle structure brings about a uniform residence time distribution, so as to ensure a homogeneous extent of reaction for the final product. The complete mathematical model for PA6 polymerization while flowing through the VK tube was established according to PA6 hydrolytic polymerization kinetics. The optimized baffle structure was shown to be compatible with the desired polymerization variables.     

PA6减压后聚合生产工艺

分析探讨了采用减压后聚合工艺生产ＰＡ６ 的可行性及实施效果。ＰＡ６ 生产中实施减压后聚合工艺能够提高反应后期的排水率、降低中心熔体温度、降低产物的低聚物含量、提高ＶＫ 管生产能力及切片的内在质量。还讨论了真空度的大小对ＰＡ６ 生产的影响。生产中真空度取－ ０．００５～－ ０．０３ Ｍ Ｐａ较为适宜。     

尼龙6/纳米蒙脱土复合材料制备及性能研究

利用活化处理的纳米蒙脱土(OMMT),通过原位插层聚合原理,控制聚合温度、压力、时间等,在聚合管实现连续化稳定制备剥离型尼龙6(PA6)/纳米OMMT复合材料;采用熔融纺丝法制得PA6/纳米OMMT复合纤维;利用X射线衍射、透射电镜(TEM)等方法分析复合材料的结构与性能。结果表明:聚合时控制水与己内酰胺质量比为3%～5%,前聚压力不超过0.4 MPa,后聚压力小于-0.040 MPa,聚合温度240～280℃,聚合时间26～30 h,可制得相对分子质量为18 000～18 600,单体质量分数小于1.6%,含水率小于450μg/g的PA6/纳米OMMT切片;TEM分析表明,纳米OMMT在PA6基体均匀分散;复合材料的力学性能有较大幅度的提高,断裂强度达102.15 MPa,比纯PA6提高了12%;PA6/纳米OMMT复合纤维性能优异,适合轮胎骨架材料的制备要求。     

PA6/蒙脱土熔融插层复合材料结构与性能分析

通过熔融共混法插层复合制备了聚酰胺(PN)6／蒙脱土纳米复合材料，测试了力学性能并对不同蒙脱土含量的PA 6／蒙脱土纳米复合材料进行了对比。实验表明，通过熔融插层可使PN 6基体插层于蒙脱土中，所得到的复合材料的性能较PN 6有很大提高。蒙脱土特殊的层状结构使得利用熔融共混在机械力的作用下插层到纳米级复合材料成为可能。     

原位聚合制备抗紫外芳香族支链锦纶6及其应用

通过添加均苯四甲酸二酐进行原位聚合制备抗紫外芳香族支链锦纶6(PA6-Ti O2)母粒,后与线型PA6进行共混纺丝,研究了抗紫外芳香族支链PA6的聚合工艺、纺丝工艺,探索支链PA6对纤维热学性能、加工性能、力学性能等的影响。结果表明:随着均苯四甲酸二酐含量的增加,芳香族支链PA6聚合熔体黏度减小,相对黏度逐渐降低,表明芳香族支链PA6的流动性增加;其结晶熔融温度逐渐降低,在相同纺丝温度下螺杆压力下降,表明可以有效改善其加工性能,但对纤维的力学性能有一定的影响;制备的抗紫外纤维在280~320 nm波长内,紫外线透过率小于10%,具有较好的紫外线遮蔽性能,从纤维断面扫描电镜(SEM)谱图可见基体相容性好。     

Preparation and characterization of graphene reinforced PA6 fiber

Here, we report the successful preparation of PA6/GO composite fibers through in situ polymerization and the melting spinning method. The results suggest that graphene has induced only minor changes on the relative viscosity yet exhibits significant effects on the crystallization characteristics. The SEM images of the fibers have shown several expended borders as a consequence of graphene addition. The maximum strength of the composite fibers (5.3 cN/dtex) has been reached 0.05 wt % graphene added to the system; the draw ratio was equaled to 3.8. Compared to the neat PA6 fiber, the fibers with graphene displayed superior creep resistance features; the creep rate constant was 0.38 at a 0.05 graphene concentration, with a draw ratio of 3.5. The approach employed in this research paves the way towards PA6/graphene nanocomposites have been prepared through in situ polymerization using caprolactam and graphene oxide/water pulp as starting materials. In situ polymerization approach facilitated a superior interaction between PA6 and graphene. Compared to graphene oxide powder, the graphene oxide in water pulp has prevented the agglomeration when added to the caprolactam melt, leading to its enhanced dispersion within the system. PA6/graphene as‐spun fiber has been produced by the mean of melt‐spinning strategy using a melt‐spinning machine, obtaining products with different draw ratios after drawing at 120 °C. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 45834.     

国内外尼龙6聚合管的差距

针对国内外尼龙６生产厂家所使用的聚合ＶＫ管进行了比较．与国外同行业相比，认为我国的聚合管无论从产量还是产品质量均处于技术落后状态，聚合管内部结构简单，所生产的产品质量差。德国Ｚｉｍｍｅｒ公司设计的ＶＫ管较先进，结构设计合理，当前在技术上处于领先水平。对国产ＶＫ管存在的问题提出一些看法。     

聚(苯乙烯-丙烯酰胺)/蒙脱土核壳结构材料改性聚酰胺6的性能研究

用自制的以有机蒙脱土（OMMT）为核、聚苯乙烯为次外层、聚丙烯酰胺为外层的新型聚(苯乙烯-丙烯酰胺)/OMMT核壳结构,通过熔融共混法制备了含3 %（质量分数,下同）核壳结构的改性聚酰胺6（PA6）。研究了改性PA6的力学性能、加工流动性能、结晶性能和热稳定性能。结果表明,核壳结构改性PA6能明显提高材料的弯曲性能,其弯曲强度较纯PA6提高了1.44 %,弯曲模量提高了3.46 %;核壳结构对PA6的结晶有成核作用,材料的结晶温度提高了8.5 oC,结晶度提高了3.3 %;核壳结构改性PA6与纯PA6具有基本一致的热稳定行为;核壳结构还能有效提高PA6的加工流动性,其熔体流动速率是纯PA6的2.18倍。     

Effects of molecular weight on the dynamic mechanical and rheological properties of anionically polymerized polyamide 6 containing nanofiber

Anionic ring‐opening polymerization of ε‐caprolactam leads to the formation of polyamide 6 (PA6). This reaction takes place at a significantly faster rate and gives a narrower molecular‐weight distribution than those obtained with other techniques. Because of this advantage, anionic polymerization of PA6 during melting was investigated in this work. In an internal mixer, PA6 was prepared via the melt polymerization of ε‐caprolactam as monomer with sodium caprolactam as a catalyst and hexamethylene diisocyanate as an activator. The effects of various concentrations of catalyst and activator on the rate of reaction and the amount of residual monomer were determined. Also, the physical and mechanical properties of PA6 prepared in this way and commercial PA6 prepared via hydrolytic processing were determined by differential scanning calorimetry and dynamic mechanical thermal analysis, as well as tensile, impact, and rheological tests. The experimental results showed that the composition which included 3% of catalyst and 3% of activator gave better properties than the other formulations. These conditions led to the lowest residual monomer content and better mechanical properties, as well. Another novel aspect of this investigation was nanofiber formation during the melt polymerization. The nanofibers had lower molecular weights than the matrix and thus created a special crystal structure different from that of the matrix. Mechanical property measurements showed that PA6 prepared by using this technique and the aforementioned formulation was similar to the commercial PA6. J. VINYL ADDIT. TECHNOL., 2010. © 2010 Society of Plastics Engineers