凯夫拉（Kevlar）为什么如此强韧？
Why is Kevlar so strong and tough?
凯夫拉是对位芳纶，分子链含刚性芳环并通过酰胺键（氢键）紧密堆砌成取向晶体。沿链方向的共价键和链间氢键共同承受外力，使其比强度超过钢。它广泛用于防弹衣和轮胎帘子线。
Kevlar is a para-aramid whose chains bear rigid aromatic rings and pack into oriented crystals via amide hydrogen bonds. Covalent bonds along the chain and interchain hydrogen bonds together bear load, giving a strength-to-weight ratio above steel. It is used in bulletproof vests and tire cords.
难度 专业 · 适合 高中(15-18)
CC BY 4.0 · 已核验 · Verified 2026-11-02
来源 · Source
潘祖仁《高分子化学》
Polymer Chemistry (Pan Zuren)
独立核验依据 · Independent verification: 核验依据 1 ISBN 9787122000248（豆瓣书目条目: 高分子化学）
#凯夫拉 #芳纶 #氢键
什么是高分子的玻璃化转变温度（Tg）？它在实际应用中有什么意义？
What is the glass transition temperature (Tg) of a polymer, and why is it important in practice?
玻璃化转变温度是高分子从硬而脆的玻璃态转变为柔软橡胶态的临界温度，此时链段运动被“解冻”。Tg决定了塑料的使用温度下限和橡胶的耐寒性——例如聚苯乙烯Tg约100℃、室温下为硬塑料，而天然橡胶Tg很低、室温呈弹性。
The glass transition temperature is the critical temperature at which a polymer changes from a hard, brittle glassy state to a soft, rubbery state as chain-segment motion 'thaws.' Tg sets the lower service-temperature limit of plastics and the cold resistance of rubbers—e.g., polystyrene (Tg ~100 ℃) is a rigid plastic at room temperature, while natural rubber has a very low Tg and is elastic at room temperature.
难度 专业 · 适合 高中(15-18)
CC BY 4.0 · 来源待核验 · Source pending review
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出处备注：著录含书名，但缺版次 / 出版社 / 年份中的一部分，需编辑补全后才能做独立比对。
何曼君等《高分子物理》（第三版），复旦大学出版社
He Manjun et al., 'Polymer Physics' (3rd ed.), Fudan University Press
独立核验依据 · Independent verification: 核验依据 1 ISBN 9787309013306（豆瓣书目条目）
#玻璃化转变 #Tg #玻璃态 #橡胶态 #链段运动
缩聚反应与加聚反应有何区别？
How does condensation polymerization differ from addition polymerization?
加聚是含不饱和键的单体直接相连、无小分子副产物（如聚乙烯）；缩聚是带两个或以上官能团的单体反应并脱去小分子（如水、醇），如尼龙-66 由二胺与二酸缩合。缩聚物常含酯、酰胺等键。
Addition polymerization links unsaturated monomers directly with no small byproducts (e.g., polyethylene); condensation polymerization reacts monomers with two or more functional groups and eliminates small molecules like water or alcohol, as in nylon-66 from a diamine and a diacid. Condensates often contain ester or amide bonds.
难度 进阶 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-11-02
来源 · Source
潘祖仁《高分子化学》
Polymer Chemistry (Pan Zuren)
独立核验依据 · Independent verification: 核验依据 1 ISBN 9787122000248（豆瓣书目条目: 高分子化学）
#缩聚 #加聚 #尼龙
橡胶的硫化（vulcanization）是怎样改善天然橡胶性能的？
How does the vulcanization of rubber improve the properties of natural rubber?
硫化是在天然橡胶（聚异戊二烯）中加入硫并加热，使硫原子在聚合物链之间形成交联桥。这些交联限制了分子链的相对滑移，从而大幅提高橡胶的弹性、强度、耐热性和抗变形能力，避免未硫化橡胶发黏、易流淌的缺点。
Vulcanization adds sulfur to natural rubber (polyisoprene) and heats it, forming sulfur cross-links between polymer chains. These cross-links restrict the relative slippage of molecular chains, greatly improving elasticity, strength, heat resistance, and resistance to deformation, overcoming the stickiness and flow of unvulcanized rubber.
难度 进阶 · 适合 高中(15-18)
CC BY 4.0 · 已核验 · Verified 2026-11-03
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美国化学会（ACS）化学史（查尔斯·固特异，1839）；潘祖仁《高分子化学》
American Chemical Society (ACS) history (Charles Goodyear, 1839); Pan Zuren, 'Polymer Chemistry'
独立核验依据 · Independent verification: 核验依据 1 ISBN 9787122000248（豆瓣书目条目: 高分子化学）；本条出处含多部著作，此标识只担保上面点名的这
#硫化 #橡胶 #交联 #聚异戊二烯 #弹性
凯夫拉为什么如此强韧？
Why is Kevlar so strong and tough?
凯夫拉是芳香族聚酰胺，分子链含刚性苯环并可形成大量链间氢键，沿链方向极其坚固，因此用于防弹与缆绳。Kwolek 在 1965 年于杜邦发明了这种芳纶纤维。
Kevlar is an aramid: rigid benzene rings line the backbone and many interchain hydrogen bonds make it enormously strong along the chain, suiting body armor and ropes. Kwolek invented the aramid fiber at DuPont in 1965.
难度 进阶 · 适合 高中(15-18)
CC BY 4.0 · 已核验 · Verified 2026-10-04
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Kwolek 1965 年专利；Odian《聚合原理》
Kwolek (1965 patent); Odian, Principles of Polymerization
独立核验依据 · Independent verification: 核验依据 1 ISBN 978-0-471-61020-5 (2004, Wiley)
#凯夫拉 #芳纶 #氢键
尼龙（nylon）是通过什么类型的聚合反应制成的？它为什么被称为“合成丝”？
By what type of polymerization is nylon made, and why is it called 'synthetic silk'?
尼龙是缩聚产物，由二元胺与二元酸（或氨基酸自身）缩合形成含酰胺键（—CO—NH—）的长链聚酰胺。其分子链间可形成氢键，赋予纤维高强度与光泽，外观和手感类似丝绸，因此被称为合成丝；尼龙由华莱士·卡罗瑟斯于1935年在杜邦公司发明。
Nylon is made by condensation polymerization of a diamine and a diacid (or self-condensation of an amino acid) into long polyamide chains containing amide bonds (—CO—NH—). Interchain hydrogen bonds give the fibers high strength and luster resembling silk, earning it the name 'synthetic silk'; it was invented by Wallace Carothers at DuPont in 1935.
难度 进阶 · 适合 高中(15-18)
CC BY 4.0 · 已核验 · Verified 2026-11-03
来源 · Source
美国化学会（ACS）与杜邦公司史料；潘祖仁《高分子化学》
American Chemical Society (ACS) and DuPont historical records; Pan Zuren, 'Polymer Chemistry'
独立核验依据 · Independent verification: 核验依据 1 ISBN 9787122000248（豆瓣书目条目: 高分子化学）；本条出处含多部著作，此标识只担保上面点名的这
#尼龙 #聚酰胺 #缩聚 #酰胺键 #卡罗瑟斯
什么是可生物降解高分子？
What are biodegradable polymers?
可生物降解高分子能在微生物或水解作用下断裂成小分子，最终进入自然循环，典型如聚乳酸（PLA）、聚己二酸/对苯二甲酸丁二酯（PBAT）。它们用于包装、医用缝合线，可缓解白色污染。但降解仍需合适条件，并非任何环境都快速分解。
Biodegradable polymers break into small molecules under microbes or hydrolysis and rejoin natural cycles; typical examples are polylactic acid (PLA) and PBAT. They serve in packaging and surgical sutures, easing plastic pollution. Yet degradation needs suitable conditions and is not rapid everywhere.
难度 进阶 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-11-02
来源 · Source
潘祖仁《高分子化学》
Polymer Chemistry (Pan Zuren)
独立核验依据 · Independent verification: 核验依据 1 ISBN 9787122000248（豆瓣书目条目: 高分子化学）
#可降解高分子 #聚乳酸 #白色污染
加聚反应是怎样把小分子连成长链的？
How does addition polymerization link small molecules into long chains?
含不饱和键的单体（如乙烯）在引发剂下打开双键，链式增长把成千上万个单元头尾相连成高分子，无副产物生成。施陶丁格在 1920 年提出高分子概念并因此获 1953 年诺奖。
Monomers with unsaturation (e.g., ethylene) open their double bonds under an initiator and chain-grow, linking thousands of units head-to-tail into a polymer with no byproduct. Staudinger proposed macromolecules in 1920 and won the 1953 Nobel Prize.
难度 进阶 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-10-04
来源 · Source
施陶丁格 1920 年论文；Odian《聚合原理》
Staudinger (1920); Odian, Principles of Polymerization
独立核验依据 · Independent verification: 核验依据 1 ISBN 978-0-471-61020-5 (2004, Wiley)
#加聚 #高分子 #链式增长
给蛋白质药物接上一条聚乙二醇链（PEG化），为什么就能明显延长它在血液中的存留时间？
Why does covalently attaching a polyethylene glycol chain (PEGylation) markedly extend how long a protein drug stays in the bloodstream?
主要因为PEG增大了药物的流体力学半径，并屏蔽了降解与识别位点。机理：肾小球按分子尺寸滤过，PEG高度水化后的表观体积远超其实际分子量对应值，原本数分钟即被肾脏排出的小型蛋白因此滞留循环；柔性的水化PEG链又如分子刷般阻挡蛋白酶接近肽键、遮蔽抗原表位，并减少肝脏与网状内皮系统的摄取。清除率整体下降，血药浓度波动收窄，给药间隔随之延长。
PEG works chiefly by inflating the drug's hydrodynamic radius and masking the sites proteases and antibodies recognize. Kidney glomeruli sieve by size, and because PEG drags along a large shell of bound water its apparent volume dwarfs what its nominal molecular weight implies, so proteins that would vanish within minutes linger in circulation. The flexible hydrated chain also behaves like a molecular brush, denying proteases access to peptide bonds, hiding epitopes, and curbing uptake by liver and reticuloendothelial tissue. Clearance falls, plasma levels smooth out, and dosing intervals stretch.
难度 进阶 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-11-04
来源 · Source
Veronese 与 Pasut,《PEGylation, successful approach to drug delivery》,Drug Discovery Today,2005 (DOI: 10.1016/s1359-6446(05)03575-0)
Veronese & Pasut, 'PEGylation, successful approach to drug delivery', Drug Discovery Today, 2005, DOI: 10.1016/s1359-6446(05)03575-0
独立核验依据 · Independent verification: 核验依据 1 Crossref DOI 10.1016/s1359-6446(05)03575-0
#PEG修饰 #流体力学半径 #长循环给药
高分子前药的Ringsdorf模型由哪几部分结构组成？各部分分别解决递药过程中的什么问题？
Which structural parts make up the Ringsdorf model of polymer prodrugs, and what delivery problem does each part solve?
模型把水溶性高分子主链、经间隔臂悬挂的药物与靶向基团三个模块连于一体，是聚合物前药设计的通用蓝图。主链提供水溶性并延长体内循环；药物通过可水解或可酶切的间隔臂偶联，被转运至病灶处切下后才恢复活性，避免偶联态失效；靶向基团如半乳糖、叶酸或抗体识别病变细胞特异受体，实现主动富集。它首次将增溶、控制释放与靶向整合进同一个分子架构，成为后续高分子载药体系的共同起点。
The model fastens three modules onto one scaffold - a water-soluble polymer backbone, drugs hung on spacer arms, and targeting groups - and stands as the general blueprint for polymer prodrugs. The backbone supplies water solubility and prolongs circulation; each drug rides a hydrolyzable or enzymatically cleavable spacer, recovering activity only after being clipped off at the lesion, since the tethered form is inactive; targeting ligands such as galactose, folate, or antibodies dock receptors unique to diseased cells for active accumulation. It first unified solubilization, controlled release, and targeting within a single molecular design, the shared starting point of later polymer carriers.
难度 进阶 · 适合 高中(15-18)
CC BY 4.0 · 已核验 · Verified 2026-11-04
来源 · Source
Ringsdorf,《Structure and properties of pharmacologically active polymers》,Journal of Polymer Science: Polymer Symposia,1975 (DOI: 10.1002/polc.5070510111)
Ringsdorf, 'Structure and properties of pharmacologically active polymers', Journal of Polymer Science: Polymer Symposia, 1975, DOI: 10.1002/polc.5070510111
独立核验依据 · Independent verification: 核验依据 1 Crossref DOI 10.1002/polc.5070510111
#高分子前药 #Ringsdorf模型 #靶向递送
热塑性塑料和热固性塑料有何不同？
How do thermoplastic and thermoset plastics differ?
热塑性塑料加热可软化重塑，分子链间主要为物理缠结（如聚乙烯、PET），可反复加工回收。热固性塑料在固化时形成交联网络（如环氧树脂、酚醛），一旦成型不可再熔，耐热性好但难回收。两者结构决定用途。
Thermoplastics soften and reshape on heating, with mainly physical chain entanglement (e.g., polyethylene, PET), and can be reprocessed. Thermosets form a crosslinked network during curing (e.g., epoxy, phenolic) and cannot be remelted, offering heat resistance but poor recyclability. Structure dictates use.
难度 进阶 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-11-02
来源 · Source
潘祖仁《高分子化学》
Polymer Chemistry (Pan Zuren)
独立核验依据 · Independent verification: 核验依据 1 ISBN 9787122000248（豆瓣书目条目: 高分子化学）
#热塑性 #热固性 #交联
什么是单体和高分子？聚合度是什么？
What are monomers and polymers, and what is degree of polymerization?
单体是能聚合成高分子的小分子重复单元，高分子（聚合物）是由大量单体连接成的巨大分子。聚合度（DP）是一条链中重复单元的平均数目，决定分子量大小。聚合度越高，材料通常越强韧。
A monomer is the small repeat unit that polymerizes into a macromolecule, and a polymer is the huge molecule built from many monomers. Degree of polymerization (DP) is the average number of repeat units per chain, setting molecular weight. Higher DP usually makes the material tougher.
难度 入门 · 适合 幼儿(3-6)
CC BY 4.0 · 已核验 · Verified 2026-11-02
来源 · Source
潘祖仁《高分子化学》
Polymer Chemistry (Pan Zuren)
独立核验依据 · Independent verification: 核验依据 1 ISBN 9787122000248（豆瓣书目条目: 高分子化学）
#单体 #高分子 #聚合度
加聚反应和缩聚反应合成高分子时有什么根本区别？
What is the fundamental difference between addition polymerization and condensation polymerization in making polymers?
加聚反应由含不饱和键的单体（如乙烯）通过打开双键相互连接成大分子，过程中不失去小分子。缩聚反应则由带两个及以上官能团的单体（如二元酸与二元胺）缩合连接，每形成一次键通常脱去一个小分子（如水或醇）。
In addition polymerization, monomers with unsaturated bonds (such as ethylene) link up by opening their double bonds into a large molecule, with no small molecule lost. In condensation polymerization, monomers bearing two or more functional groups (such as a diacid and a diamine) join by condensation, typically releasing a small molecule (water or alcohol) at each linkage.
难度 入门 · 适合 小学高段(9-12)
CC BY 4.0 · 已核验 · Verified 2026-11-02
来源 · Source
潘祖仁《高分子化学》（第五版），化学工业出版社
Pan Zuren, 'Polymer Chemistry' (5th ed.), Chemical Industry Press
独立核验依据 · Independent verification: 核验依据 1 ISBN 9787122000248（豆瓣书目条目: 高分子化学）
#加聚 #缩聚 #高分子 #单体 #官能团