聚酯纤维——聚酯合成

聚酯是制造聚酯纤维、涂料、薄膜及工程塑料的原料，是由饱和的二元酸与二元醇通过缩聚反应制得的一类线性高分子缩聚物。这类缩聚物的品种因随使用原料或中间体而异，故品种繁多数不胜数。但所有品种均有一个共同特点，就是其大分子的各个链节间都是以酯基“－COO－”相联，所以把这类缩聚物通称为聚酯。以聚酯为基础制得的纤维称为涤纶，是三大合成纤维（涤纶、锦纶、腈纶）之一，是最主要的合成纤维。

J. R. Whinfield (left) and J. T J. R. Whinfield (left) and J. T. Dickson (right) re-enact the discovery of fibre-forming poly(ethylene terephthalate) (photograph circa 1942)

n PET纤维制备流程

流程 间歇法 连续法 连续法流程图： 冷凝水 TPA粉末 料仓 浆料混合槽 EG配料槽 中间槽 催化剂 第一酯化器 第二酯化器 第三酯化器 第一酯化器 第二酯化器 第三酯化器 EG配料槽 （酯化率82%） （酯化率92%）（酯化率>99.4%） 中间槽 催化剂

聚对苯二甲酸乙二酯（PET）的生产 缩聚反应平衡 a. BHET羟乙酯基与聚合体分子羟乙酯基的可逆平衡逐步反应 b. 聚合体间羟乙酯基相互进行缩合反应

连续法缩聚 流程图

Simplified flow sheet of a multi-purpose discontinuous PET plant Simplified flow sheet of a multi-purpose discontinuous PET plant. Frommanufacturer’s literature published by Zimmer AG and reproduced with permission

Discontinuous polycondensation reactors: (a) conventional design for capacities up to 35 t/d; (b) novel discontinuous disc-ring reactor for capacities up to 100 t/d . From manufacturer’s literature published by Zimmer AG and reproduced with permission

Typical process data and polymer properties for a polycondensation batch plant: temperature, 285 ◦C (maximum); pressure, 1mm Hg; catalyst, 200ppm Sb2O3 (based on PET)

Continuous PET process based on TPA with four reactors in series

Continuous PET process based on TPA with five reactors in series [2] Continuous PET process based on TPA with five reactors in series [2]. From manufacturer’s literature published by Zimmer AG and reproduced with permission

Horizontal perforated disc-ring prepolycondensation reactor Horizontal perforated disc-ring prepolycondensation reactor.From manufacturer’s literature published by Zimmer AG and reproduced with permission

Medium-viscosity cage-type finisher. From Shaw, G. , Schaller, R. A Medium-viscosity cage-type finisher. From Shaw, G., Schaller, R. A., Stikeleather, W. J., Melton, M. D.,

Medium-viscosity disc-type finisher [2]. From manufacturer’s literature published by Zimmer AG and reproduced with permission

High-viscosity double-drive disc-type finisher with two different stirrer frequencies . From manufacturer’s literature published by Zimmer AG and reproduced with permission

Comparison of the various PET-SSP processes: F , fluidization; M , mechanical agitation

Schematic of the Buhler PET-SSP process for technical fibres:H , heater

Layout of an SSP batch process reactor Layout of an SSP batch process reactor. From manufacturer’s literature published by OHL Apparatabau and Verfahrenstechnik, Limburg, Germany, and reproduced with permission

连续式N2保护法——经干燥和预结晶的切片从顶端进入圆筒形反应器，在210-225℃下，物料在反应器内呈活塞状、借助重力极缓慢地向下移动，连续通入反应器的热N2气流与切片进行热质交换，将反应生成的小分子带出反应系统，经N2净化系统去除带出的小分子后再投入循环使用。连续式工艺产量大，适于大规模工业生产。 间歇式真空法——真空转鼓中聚合

Mechanism for the thermal degradation of PET

Degradation mechanism for PET in the presence of oxygen, as proposed by Edge et al.

Intrinsic viscosity of the polymer melt as a function of extruder residence time and temperature for an initial water content of 3ppm

Intrinsic viscosity of the polymer melt as a function of extruder residence time and initial water content for a temperature of 280 ◦C

Concentration of carboxyl end groups as a function of extruder residence time, temperature and initial water content

Polydispersity index for different PET processes and reactor sizes. GPC conditions: TCM/HFIP (98:2); columns PSS SDV10 (105 A° ) and SDV5 (500 A° );detection, UV (269 nm) and RI; polystyrene calibration

热媒炉区及热媒输送  EG储罐 聚酯生产车间 切片包装 聚酯中央控制系统 切粒机

聚酯生产原料-EG贮罐 酯化反应器搅拌系统采用进口装置                                         回用EG净化系统 二次热媒系统采用低噪无泄漏屏蔽泵 真空系统采用整套进口设备 全套进口的熔体过滤器

聚酯生产线的关键设备-终聚釜 熔体输送泵采用进口设备 采用进口切粒机系统在稳定运行 聚酯切片成品库

名词解释 1、酯交换 2、直接酯化 3、固相缩聚 问题 1、试比较酯交换法和直接酯化法有异同（反应式、优缺点） 2、为什么聚酯缩聚反应后阶段分子量提高很困难，生产上采用什么办法解决？