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<正>根据郑州电视台网站的业务发展需求,结合现在最新的技术和网络媒体发展趋势,本文,笔者提出了郑州电视台新媒体系统的设计思路,希望能够给郑州电视台网站的整体改造提供有益的建议。郑州电视台新媒体系统建设目标是构建郑州电视台门户网站的整体框架,为今后发展提供系统管理、升级和扩充的平台,重     

STUDIES ON SEQUENCE STRUCTURE OF PET/PHB COPOLYESTERS

In this paper,the sequence distribution in the copolyester made from polyethyleneterephthalate (PET) and p-hydroxybenzoic acid (PHB) at 290℃has been investigated by 400MHz ~1H-NMR.It has been found that reference factor m of PET/PHB copo!yester linearly de-creases when PHB molar fraction increases.In addition,a series of sequence structure parameters,such as PET,PHB segment mean length,randomness,etc.are calculated from a probability modelby m,X_(PHB)%.This copolyester made at 290℃ is found to be nearer to that of completely randomcopolymer compared with that of the eopolyester made at 270℃,as in the case of the generalcopolycondensation.PHB-rich phase is formed only when PHB per number≥4,basing on thisconclusion,we establish the relationship between theoretical contents of PHB-rich phaseW_(PHB)% and PHB contents X_(PHB)% :W_(PHB)%=104.0X_(PHB)~(4.40) The minimum PHB-rich phase con-tent forming liquid crystal phase is 1.1% wt.     

2,3,5-三甲基氢醌、对苯二甲酸、2,6-萘二甲酸类聚芳酯液晶的研究

本文合成了一类以2,3,5-三甲基氢醌(TMHQ)、对苯二甲酸(TPA)、2,6-萘二甲酸(2,6-NDA)为基本共聚单体并加有少量聚对苯二甲酸乙二酯(PET)的芳香共聚酯;研究了共聚酯的组成对溶解度、热性质、液晶性质、流变性质及晶体结构的影响。实验表明,共聚酯在某个温度范围内呈现向列型液晶的特征,其熔体粘度的切变依赖特性也证实了这一点。DSC 热谱和广角 X-射线衍射图分析证明,对某些组成,在共聚酯的分子链中存在着相应于 TMHQ-TPA 和 TMHQ-2,6-NDA 两种短嵌段结构。这是与非均相缩聚条件有关的。     

聚氨酯-聚丙烯腈共混体系的两相结构及一些有关的生物性质

本文通过DDV、DSC等测试手段,研究了聚氨酯-聚丙烯腈共混体系的两相结构以及一些有关的生物性能.发现在该共混体系中,聚氨酯硬段与聚丙烯腈之间存在一定程度的相互作用.对该共混物进行的性能测试结果表明,聚氨酯与聚丙烯腈共混以后,其抗霉性有显著提高.并且这种共混聚氨酯在碱性介质中水解后,亲水性显著提高,血液相容性也有所改善.     

KINETICS AND MECHANISM RELATING ALKALINE HYDROLYSIS OF POLYESTER BLEND FIBER

Cation Dyeable Polyester(CDP)was made by copolymerizing dimethyl terephthalate(DMT),S-sodium sulfonate dimethyl isophthalate(SIPM) with a weight fraction of 4.5% and ethyleneglycol (EG).Blend of PET and CDP was spun into hollow fiber.The fiber was then treated withaqueous NaOH.In this paper,kinetics and mechanism of alkaline hydrolysis of PET,CDP andtheir blend PET/CDP fiber were studied by means of specific area measurement,scantling elec-tron microscopy and other chemical analyses.It was showed that the rate of alkaline hydrolysis isCDP>PET/CDP>PET.Because of blending effect,the alkaline hydrolysis of PET/CDP is dif-ferent from that of PET.CDP phase in the PET/CDP fiber is predominantly hydrolyzed,andhence some pieces of fiber(micro-fiber) fall off the fiber because of etching.     

MOLECULAR CHAIN STRUCTURE AND CRYSTALLINE STRUCTURE OF PB-ET COPOLYESTER

The molecular chain structure and crystalline structure of PB-ET copolyester made by con-densation polymerization are studied by means of ~(13)C nuclear magnetic resonance spectroscopy(~(13)C NMR),dynamic mechanical analysis (DMA),wide angle X-ray scattering (WAXS),depolarized light intensity (DLI) and stress-strain measurement(S-S).It is shown that PB-ETcopolyester is a random copolymer.Because of different ratios of EG(ethylene glycol)to BD(butane diol)in the copolyester,its crystalline forms and mechanical properties vary remarkably.With the increasing amount of BD,its crystallization kinetic parameters n,k and t_(1/2)~(-1) increaserapidly.When EG/BD equals 25/75 (mole ratio),the copolyester has αβ transition as PBTdoes.     

潜在交联剂MDI-丙酮肟加成物的合成及其在氨纶纺丝原液中的稳定性(简报)

将聚酯(或聚醚)/4.4'一二苯基甲烷二异氰酸酯(MDI)/间苯二胺嵌段共聚物在 DMF中的浓溶液(即氨纶纺丝原液)以水为凝固浴进行纺丝,可以制得高弹性的氨纶。为了改善氨纶的力学性能,交联变性是重要手段之一。由于大分子链硬段上有活泼氢存在,可以使用二异氰酸酯(例如 MDI)与之反应来达到交联的目的。     

涤纶高速纺丝速度对纤维结构及性能的影响

在涤纶高速纺丝各种工艺参数中,纺丝速度是决定纤维结构的最重要的因素。预取向丝的动态力学温度谱的α内耗峰,随着纺速增加,呈现规律性的变化。随纺速增加,预取向丝的α内耗峰由峰值较高、峰形尖而窄过渡到峰值较低、峰形钝而宽。随纺速增加,储能模量略有增长,纺速在3000米/分—4000米/分时,出现了迭加的α内耗峰,反映了非晶态两种不同类型的分子链段的运动。密度、双折射和声速等的测试结果,都说明预取向丝随纺速增加从较低的取向和较低的结晶朝较高的取向和较高的结晶的结构变化。这和动态力学试验是极相吻合的。本文还提到,预取向丝的动态力学温度谱的α内耗峰与其储能模量,纤维的力学性质、强度、伸度、屈服应力、初始模量及其他结构参数间有很好的相关性。     

含萘环共聚芳酯的分子链结构及热稳定性

本文以对羟基苯甲酸、2,7-萘二酚、对苯二甲酸和少量的聚2,6-萘二甲酸乙二酯为单体制备了一系列具有不同配比的液晶共聚芳酯。用红外光谱法、直接裂解质谱法和裂解气相色谱法鉴定了共聚芳酯的分子链结构,指出共聚芳酯的分子链结构与所加5种单体链节结构基本一致。借助于热重分析仪研究了共聚芳酯的热稳定性及其与分子链结构之间的关系。结果表明:在空气介质中该共聚芳酯开始裂解的最低温度为320℃,裂解反应速度最快时的温度均高于490℃;并且发现,共聚芳酯的分子链结构对热稳定性有较明显的影响,链结构规整性好的共聚芳酯具有较高的热稳定性。实验结果指出,共聚芳酯在空气及氮气介质中的热裂解反应均分两步完成。正像文中的3号样品,空气中的第一步裂解反应在326℃开始发生,第二步裂解反应则发生在540℃左右。本文还探讨了共聚芳酯的热裂解机理。     

Latice Deformation and Meso-Phase Structure in Poly(Ethylene Terephthalate)From Solid State Coextrusion

The development of crystalline and Meso-phase structure by solid state extrusion from50℃ to 90℃ is studied for PET. The unit cell parameters of stress-induced crystallites inextrudates are determined as a function of extrusion draw ratio (EDR), and ext