化学学科核心素养引领下的水溶液大单元教学设计与实践*

通过新旧课标与教材的对比分析,确定水溶液主题的认识方式、大概念和教学目标,围绕教学目标选择合适的情境素材,以大概念统领单元教学,在真实问题的解决过程中发展学生认识水溶液的基本角度和思路,促进学生化学学科核心素养的发展。     

高分子合成教学实验改革初探

为使我系高分子专业本科毕业生和硕士生适应我国社会主义现代化建设和改革、开放的需要,我系高分子合成教学实验室在系和高分子教研室的支持下,对四年级本科生和部分硕士研究生的“高分子合成实验”以及另一部分硕士研究生的“教学实践”等课程进行了一些改革。经过两年多的探索,这些改革收到了良好的效果。     

专题讨论与“高分子物理”之深化理解及运用

深化理解“高分子物理”的概念与原理并能运用自如，无论是对本课程的学习，还是从事相关研究或实际工作，都是十分有利的。为此，笔者结合多年教学实践提出了采取专题讨论的方式，以增加学生在教学中的主体权重，使其在积极参与的过程中，“活学活用”、充分提升认识，达到良好的教学效果。     

夯实基础、理清脉络、充实内容,讲透高分子结构

高分子结构是高分子性能的基础,高分子结构知识也是学生学习高分子科学知识的起点与基础,高分子结构包含一、二、三、四级结构,一级结构具有更重要的基础性决定作用,是高分子结构的基础;二级结构的多样性是高分子特性的重要表现,它与一级结构一起共同决定高分子的高次结构与性能。在高分子物理的教学过程中,注重高分子结构的基础作用,用清晰的高分子结构知识脉络,辅以已经市场检验的具有优异性能的高分子产品的结构知识,讲解高分子结构对其性能的决定性作用,可以夯实学生对高分子结构基础性作用的认识,达到讲透高分子结构的目的。     

学科交叉背景下的高分子材料与工程专业的教学探索与实践——以浙大高分子科学与工程学系专业核心课程《高分子化学》教学为例

自从20世纪20年代“高分子”概念建立之后,高分子学科和工业蓬勃发展,人类进入了高分子材料的新纪元。高分子材料在民生、安全和尖端科技等各个领域发挥着关键作用。作为全球制造业最大的国家,我国未来要在全球高分子材料领域处于引领地位,关键在于当前的大学基础教育要能培养出德才兼备的顶尖专业人才。浙江大学高分子科学与工程学系的高分子材料与工程专业具有典型的理工学科交叉性特征。本文结合该专业的核心必修课程《高分子化学》教学改革的例子,总结专业建设的探索和实践经验,探讨学科交叉背景下专业人才培养的两个基本问题：一是以培养理工结合型专业人才为目标的课程体系设置与建设,另一个是厚植正确价值观作为人才培养基石的课程教学实践。希望本文作者的教学实践经验和思考能为我国高分子材料与工程专业人才培养起到“抛砖引玉”的作用。     

“高分子物理”课程教学中的整体性思路初探

在"高分子物理"课程教学中,主要难点是教学内容比较繁杂,所涉及的概念很多且较抽象,各种高分子材料的结构和性能差异性大,不易把握其共性。以高分子结构、性能和分子运动的中间态,即高分子链的远程结构中分子链的形态、高聚物性能的高弹性和链段运动为基础,避开繁杂抽象的具体概念,以简洁的方式来呈现高分子物理的教学内容,帮助学生在渐进的教学过程之初便建立一个形象化的整体性思路,以此作为后续教学的指导性思路,在整个教学过程中进一步展开和强化,教学效果很好。     

《高分子化学》聚合机理教学中有机化学知识的衔接利用

高分子化学是在有机化学基础上发展而成一门学科,高分子的合成反应与有机小分子的合成反应密切相关,特别是高分子合成反应机理的学习中大量应用到有机化学的基础知识.因此,在高分子化学教学中有效利用有机化学知识是帮助学生更好理解和掌握高分子化学反应机理相关知识的关键.本文根据笔者教学实践,从烯类单体聚合活性及机理、自由基聚合阻聚机理、配位聚合机理等方面以实例形式探讨了如何利用有机化学知识帮助解释高分子化学中反应活性及反应机理.     

“进入合成有机高分子化合物的时代”单元整体设计与教学实践

选取聚乙烯醇滴眼液和维纶纤维为教学素材,对"进入合成高分子化合物的时代"一章进行了全新的单元整体设计和教学实践。按照高分子化学、高分子物理和高分子工程3个专业体系对教学内容进行了整合,创设情境、提出问题,使学生在思考、讨论和实验中获取新知,认识到高分子科学与工程的一般性研究方法,以及高分子化合物组成、结构、性质和用途间的关系。     

功能高分子

本文简述了功能高分子的发展,合成途径以及所谓的高分子效应。对该领域内所涉及的各类功能高分子的性质、合成、应用及发展前景等作了概要介绍。内容包括具有分离功能的高分子、高分子试剂、高分子催化剂、光活性高分子、磁性高分子、能量转换及储能材料、生物医用材料、高分子药物、高分子液晶及一些其他功能高分子材料。     

在"高聚物的结构与性能"课程中应该引入的几个新概念

在“高聚物的结构与性能”课程教学中，很有必要向学生介绍高分子科学近十几年来的发展，尤其是在高分子凝聚态基本物理问题上的研究成果以及相关的新概念、新知识，特别是我国学者的贡献。本文较为详细地讨论了近年来作者在教学中介绍的几个新概念，如：动态接触浓度、单链凝聚态、凝聚缠结等。     

智能高分子材料在智能给药系统中的应用

简要介绍了合成智能高分子材料、半合成智能高分子材料和天然智能高分子材料在智能给药系统中的应用研究进展,并展望了其在智能给药系统中的应用前景。     

智能高分子材料在智能给药系统中的应用

简要介绍了合成智能高分子材料、半合成智能高分子材料和天然智能高分子材料在智能给药系统中的应用研究进展,并展望了其在智能给药系统中的应用前景.     

Semi-fluorinated polyarylenes: Microwave-assisted synthesis and structure–property relationships

A series of three fluorine containing and three non-fluorinated Diels–Alder step-growth polyarylene polymers and copolymers was synthesized via conventional oil bath heating (days/weeks). A drastic time reduction was realized with a microwave-assisted polymerization (hours). The polymers were characterized by multinuclear (¹H, ¹³C, and ¹⁹F) NMR and attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy, thermal analysis (thermogravimetric analysis [TGA], differential scanning calorimetry [DSC], and dynamic mechanical analysis [DMA]), gel permeation chromatography, X-ray diffraction (XRD), water contact analysis, and refractive index (RI) measurements. The NMR spectra indicated a mixture of para and meta conformations through the polymer backbone increasing to more para with greater fluorine content. TGA revealed the fluorine-containing polyarylenes possessed the highest char yields at almost 80% at 1000°C under nitrogen, and all the polyarylenes possessed onset of degradation temperatures above 550°C under nitrogen and air atmospheres. XRD analysis indicated more ordering for the fluorine-containing polyarylenes which afforded the high char yields. DMA gave storage moduli values in the range of 1–10 GPa for the polyarylenes. Molecular weights for all samples were above 100 kg/mol. Water contact angles did not change with fluorine content due to the shielding effect of the pendant phenyl groups. However, the RI decreased to 1.6497 at 632.8 nm for the polyarylene with the highest fluorine content.     

Modification of Particle Filled Polymers with High Energy Electrons Under In-Stationary Conditions of Melt Mixing

Summary: Polymer modification with high energy electrons is well-established in polymer industry and used for degradation, cross-linking, grafting, curing, and polymerization. These applications use local and temporal precise input of energy in order to generate excited atoms or molecules and ions for subsequent molecule changes via radical induced chemical reactions. In the present study, high energy electrons have been used to modify polyolefine (polyethylene and polypropylene) systems in presence of a grafting agent under stationary and in-stationary conditions. Polymer modification with high energy electrons under stationary conditions characterizes a process where required absorbed dose is applied to polymers in solid state and at room temperature. Polymer modification with high energy electrons under in-stationary conditions is a novel process where required absorbed dose is applied in molten state during melt mixing process. In this novel process, the penetration depth of electrons is limited to a part of mixing volume. The total mixing volume is modified due to the change of polymer mass within the penetration depth of electrons during mixing process. A 1.5 MeV electron accelerator has been directly coupled to a banbury mixing chamber in order to study this novel process. In comparison to the stationary process, the main differences are working at higher temperature, absence of any crystallinity, intensive macromolecular mobility as well as intensive mixing during dose application. The influence of both processes on mechanical properties and flame resistance of polymer composites is discussed.     

Synthesis of novel cyclic olefin polymers with excellent transparency and high glass‐transition temperature via gradient copolymerization of bulky cyclic olefin and cis‐cyclooctene

Novel cyclic olefin polymers (COPs) with excellent transparency and high glass‐transition temperature (T_g) synthesized from bulky norbornene derivative, exo‐1,4,4a,9,9a,10‐hexahydro‐9,10(1',2')‐benzeno‐l,4‐methanoanthracene (HBMN), and cis‐cyclooctene (COE) by ring‐opening metathesis copolymerization utilizing the “first‐generation Grubbs” catalyst, RuCl₂(PCy₃)₂(CHPh), and subsequent hydrogenation was reported herein. To get amorphous copolymers, it was of great importance to control the feed ratios and the polymerization time for gradient copolymerization. All these copolymers showed very high T_gs (141.1–201.2 °C), which varied with the content of HBMN. The films of the gradient copolymers with only one T_g were highly transparent. On the contrary, all the block copolymers synthesized through sequential addition showed two thermal transition temperatures, T_g and melt temperature (T_m), and the films of these block copolymers were opaque. The mechanical performances of the COPs were also investigated. It is the first report that transparent COP could be prepared from bulky norbornene derivative and monocyclic olefin. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 3240–3249     

Synthesis of cyclic olefin polymers with high glass transition temperature by ring‐opening metathesis copolymerization and subsequent hydrogenation

Novel cyclic olefin polymers (COPs) derived from bulky cyclic olefin, exo‐1,4,4a,9,9a,10‐hexahydro‐9,10(1′,2′)‐benzeno‐l,4‐methanoanthracene (HBMN), with high glass transition temperature (T_g), excellent thermal stability, high transparency, and improved mechanical performance, have been achieved by ring‐opening metathesis polymerization and subsequent hydrogenation. The “first‐generation Grubbs” catalyst, RuCl₂(PCy₃)₂(CHPh) (Cy = cyclohexyl) ( G1 ), displays very high activity for homo/copolymerization with complete conversion. Homopolymer of the HBMN after complete hydrogenation showed a highest T_g of 223.6 °C. Copolymerization of HBMN with tricyclo[4.3.0.12,5]deca‐3‐ene or 5‐n‐hexylnorbornene was also carried out. These two series of COPs were characterized by gel permeation chromatography, nuclear magnetic resonance, differential scanning calorimetry, and thermogravimetric analysis. The T_g of the resulted COPs linearly increased with HBMN content, which is easily controlled by changing feed ratios. The tensile test indicates that these copolymers have good mechanical performance as all these copolymers show a higher strain at break compared with commercial products (TOPAS^®). © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 2654‐2661     

Processing of aromatic thermosetting copolyesters into foams and bulk parts: characterization and mechanical properties

Fully dense sheets of aromatic thermosetting copolyester (ATSP) have been produced by blending ATSP oligomers, curing the blend to produce foam, grinding the cured material to a powder, followed by sintering of the cured powers via hot press. The resulting product possesses an excellent combination of mechanical strength and high‐temperature performance to help improve part functionality, gain long‐term reliability, and cost savings. Dynamic mechanical analysis of this system featured a glass transition higher than most available performance thermosets and thermoplastic polymers or reversible bonding polymer system described in literature. Compression and tensile properties of the foam and fully dense ATSP structures exceed those of most engineering polymers. Copyright © 2016 John Wiley & Sons, Ltd.     

Reactive EB Processing of Polymer Compounds

Polymer modification with high energy electrons is well-established in polymer industry and used for degradation, cross-linking, grafting, curing, and polymerization. These applications use local and temporal precise input of energy in order to generate excited atoms or molecules as well as ions for subsequent molecule changes via radical induced chemical reactions. Reactive electron beam (EB) processing combines melt mixing process and chemical reaction simultaneously. For this purpose, a 1.5 MeV electron accelerator was directly coupled to an internal mixer in order to induce chemical reactions by energy input via high energy electrons under dynamic conditions of melt mixing of different polymer compounds. In the present study, reactive EB processing was used for the development of a flame retardant polyethylene composite as well as Thermoplastic Vulcanizate. The influence of absorbed dose as well as electron energy and electron treatment time was studied. Increased values of both tensile strength and elongation at break of polymer compounds indicated in-situ compatibilization upon reactive EB processing.     

导电性高分子电解合成的进展

本文叙述了导电性高分子电解合成的方法和应用的进展。     

自增强高性能聚合物的成型工艺同力学性能间相关性研究——1.超高分子量聚乙烯的应力诱导结晶理论和其自增强作用

本文发展了一种高分子量聚合物熔融体的应力诱导结晶结构形态模型,它是由微晶聚集体(以下简称微区)-高分子链组网和缠结网的网络结构组成。基于上述模型,把二种网中的单个链组作为独立的统计单元和形变单元,计算了二种网中单个链组的末端距分布函数,进一步计算了二种网和总网的形变自由能。在此基础上,讨论了诱导结晶结晶机理和自增强聚合物网络自由能的依赖性,并着重地研究了超拉伸高聚物的起始熔点拉伸比间的关系。用超高分子量聚乙烯膜和超取向高密度聚乙烯纤维的起始熔点和拉伸比的实验数据进行处理,得到理论予期的近似直线关系,初步验证了聚合物网应力诱导结晶理论。