異戊二烯


































































































異戊二烯





IUPAC名
2-Methyl-buta-1,3-diene
英文名
Isoprene
识别

CAS号
78-79-5  ✓

PubChem
6557

ChemSpider
6309

SMILES


InChI


InChIKey
RRHGJUQNOFWUDK-UHFFFAOYAS

ChEBI
35194

KEGG
C16521
性质

化学式
C5H8

摩尔质量
 68.12 g·mol⁻¹
外观
 無色液體

密度
 0.681 g/cm3

熔点
 -145.95 °C

沸点
 34.067 °C

溶解性（水）
 0.07 g/100 mL

折光度n
D
 1.4205-1.4225
危险性

欧盟危险性符号


有毒有毒 T


极易燃极易燃 F+



警示术语
 R：R12-R45-R52/53-R68

安全术语
 S：S45-S53-S61

NFPA 704

NFPA 704.svg

4

1

2

 

闪点
 -48°C
若非注明，所有数据均出自一般条件（25 ℃，100 kPa）下。

異戊二烯，IUPAC名称2-甲基-1,3-丁二烯，是一種共軛二烯烃，分子式为C5H8。对于天然产物萜类化合物，就是以分子中含有的异戊二烯单元个数分类的。由一个异戊二烯单元组成的萜称为半萜，两个单元组成的称为单萜，依此类推。




目录






  • 1 性質


  • 2 污染爭議


  • 3 工業用途


  • 4 参见


  • 5 參考來源





性質


異戊二烯本身是為不溶於水的無色液體，但能與乙醇、乙醚、丙酮和苯等溶劑混溶。且易自身聚合，也易與別的不飽和化合物共聚合。若在齐格勒-納塔催化劑下聚合，則會產生聚異戊二烯，也就是我們說的天然橡膠。具有優秀的彈性、張力等。少量異戊二烯與異丁烯共聚，會產生丁基橡膠。



污染爭議


有一些植物中的萜烯會產生成異戊二烯。所謂的異戊二烯和單一芬多精大多都是由樹木所產生。屬於揮發性有機碳氫化合物(VOC)，且具有一定的抗氧化、殺菌並維護樹木本身的健康，一天當中，又以中午時段排放量較大。一般我們所知道的甲醛、三氯乙烯、甲苯、乙苯等都屬於揮發性有機物，而植物所排放的芬多精其實也都是有機化合物。前提是，異戊二烯必須要在光合作用下產生，當氣溫達35℃以上，樹木就會釋放出大量的異戊二烯和一種單一芬多精，同時也促進臭氧的產生。當環境中異戊二烯排放量增加到兩倍時，臭氧平均濃度增加4ppb。


然而，事實上已有證據顯示，相互作用後，產生臭氧，會形成空氣污染。但對人體有益或有害尚且未得到科學證實。



工業用途


在常見的工業上，會經由異戊烷或者甲基丁烯催化去氫來生產、也會從輕油裂化生產乙烯所得的副產物中取出、以及用丙烯合成。丙烯在三烷基鋁下二聚，所產生的2-甲基-1-戊烯在酸性催化劑下異構化為2-甲基-2-戊烯，分解成異戊二烯和甲烷。



参见


  • 天然橡膠


參考來源



  • Reimann, S., Calanca, P. and Hofer, P., The anthropogenic contribution to isoprene concentrations in a rural atmosphere. Atmospheric Environment 34 109-115(2000).

  • Sharkey T. D., and Singsaas E. L., Why plants emit isoprene. Nature 374:769(1995).

  • 吳金村，行政院農委會-林業研究專訊，森林釋出異戊二烯對大氣品質之影響，2004


























  • 查

  • 论

  • 编


烯烴

單烯烴

C2H4 · C3H6 · C4H8 · C5H10 · C6H12 · C7H14 · C8H16
二烯烴

C3H4 · C4H6 · C5H8
多烯烴
C6H8
環烯烴

C3H4 · C4H6 · C5H8 · C6H10 · 更多




规范控制

  • NDL: 00576150



Comments

Post a Comment

Popular posts from this blog

Information security

Image
This article is part of a series on Information security Related security categories Internet security Cyberwarfare Computer security Mobile security Network security Threats Computer crime Vulnerability Eavesdropping Malware Spyware Ransomware Trojans Viruses Worms Rootkits Bootkits Keyloggers Screen scrapers Exploits Backdoors Logic bombs Payloads Denial of service Defenses Computer access control Application security Antivirus software Secure coding Secure by default Secure by design Secure operating systems Authentication Multi-factor authentication Authorization Data-centric security Encryption Firewall Intrusion detection system Mobile secure gateway Runtime application self-protection (RASP) v t e Information security , sometimes shortened to InfoSec , is the practice of preventing unauthorized access, use, disclosure, disruption, modification, inspection, recording or destruction of information. Th...
Read more

Volkswagen Group MQB platform

Image
The Volkswagen Group MQB platform is the company's strategy for shared modular design construction of its transverse, front-engine, front-wheel-drive layout (optional front-engine, four-wheel-drive layout) automobiles. Volkswagen spent roughly $60bn [1] developing this new platform and the cars employing it. The platform underpins a wide range of cars from the supermini class to the mid size SUV class. MQB allows Volkswagen to assemble any of its cars based on this platform across all of its MQB ready factories. This allows the Volkswagen group flexibility to shift production as needed between its different factories. Beginning in 2012, Volkswagen Group marketed the strategy under the code name MQB , which stands for Modularer Querbaukasten , translating from German to "Modular Transversal Toolkit" or "Modular Transverse Matrix". [2] [3] MQB is one strategy within VW's overall MB (Modularer Baukasten or modular matrix) program which also includes th...
Read more

Daniel Guggenheim

Image
Daniel Guggenheim 1925 photo Born ( 1856-07-09 ) July 9, 1856 Philadelphia, Pennsylvania Died September 28, 1930 (1930-09-28) (aged 74) Port Washington, New York Alma mater Peirce College Known for Battle for control of ASARCO Daniel Guggenheim Medal Spouse(s) Florence Shloss Children Meyer Robert Guggenheim Harry Guggenheim Gladys Eleanor Guggenheim Parent(s) Meyer Guggenheim Barbara Guggenheim Daniel Guggenheim, 1910 Daniel Guggenheim (July 9, 1856 – September 28, 1930) was an American mining magnate and philanthropist, and a son of Meyer and Barbara Guggenheim. Contents 1 Biography 2 Personal life 2.1 Aviation 2.2 Alaska 3 See also 4 References 5 Further reading 6 External links Biography Born and raised in Philadelphia, Daniel Guggenheim was sent to Switzerland as a young man to study the Swiss lace and embroidery business, and to serve as a buyer for his father's import firm. The...
Read more