The synthesis and catalytic activity of polymeric compounds containing alkali metals

Glukhovskoi, V.S.; Litvin, Yu. A.; Gainulin, I.F.

doi:10.1016/0032-3950(75)90165-3

Cited by 2 publications

(1 citation statement)

References 3 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Other initiators using lithium, sodium, and potassium have been studied [69], finding that the reaction product of these alkali metals with thiobenzophenone in tetrahydrofuran gives a soluble initiator, generating 68-75% of 3,4 structures and no 1,4 structures [54,70]. The reaction product of sodium, potassium, rubidium, or cesium with poly(p,p -biphenyleneethylene) in benzene or THF is another initiator [71]. The potassium-reaction product yields 60% of trans-1,4-, 30% of 3,4-, and 10% of cis-1,4-isoprene units.…”

Section: Polymerization Of Isoprene Using Alkali Metalsmentioning

confidence: 99%

Synthetic Polyisoprene Rubber as a Mimic of Natural Rubber: Recent Advances on Synthesis, Nanocomposites, and Applications

Cruz-Morales,

Gutiérrez-Flores,

Zárate-Saldaña

et al. 2023

Polymers

View full text Add to dashboard Cite

Up to now, rubber materials have been used in a wide range of applications, from automotive parts to special-design engineering pieces, as well as in the pharmaceutical, food, electronics, and military industries, among others. Since the discovery of the vulcanization of natural rubber (NR) in 1838, the continuous demand for this material has intensified the quest for a synthetic substitute with similar properties. In this regard, synthetic polyisoprene rubber (IR) emerged as an attractive alternative. However, despite the efforts made, some properties of natural rubber have been difficult to match (i.e., superior mechanical properties) due not only to its high content of cis-1,4-polyisoprene but also because its structure is considered a naturally occurring nanocomposite. In this sense, cutting-edge research has proposed the synthesis of nanocomposites with synthetic rubber, obtaining the same properties as natural rubber. This review focuses on the synthesis, structure, and properties of natural and synthetic rubber, with a special interest in the synthesis of IR nanocomposites, giving the reader a comprehensive reference on how to achieve a mimic of NR.

show abstract

Section: Polymerization Of Isoprene Using Alkali Metalsmentioning

confidence: 99%

Synthetic Polyisoprene Rubber as a Mimic of Natural Rubber: Recent Advances on Synthesis, Nanocomposites, and Applications

Cruz-Morales,

Gutiérrez-Flores,

Zárate-Saldaña

et al. 2023

Polymers

View full text Add to dashboard Cite

show abstract

Isoprene Polymers

Senyek

2008

Encyclopedia of Polymer Science and Technology

View full text Add to dashboard Cite

Isoprene was first isolated from the pyrolysis products of natural rubber. The first preparation of polyisoprene was reported in 1879. In 1950, the goal of preparing synthetic cis 1,4‐polyisoprene as a counter part to natural rubber was achieved. Attention was then focused on commercial preparation of isoprene for polymerization use. Shortly after the discovery of stereospecific catalysts, the first commercial polyisoprene plant came on stream in 1959–1960 using a lithium catalyst. Isoprene is a reactive diene that undergoes cycloaddition, electrophilic, nucleophilic, free‐radical, and coordinated catalytic addition, and thermal dimerization. Information on the production of isoprene by naphtha cracking as well as the synthetic processes is detailed. Depending on the catalyst and conditions, isoprene may undergo 1,2,3,4, or 1,4 addition leading to several isomeric structures. Coordination catalysts, alkali metal catalysts, and Alfin catalysts are important for polymerization and are discussed. Chemical modification of polymers is a convenient way of altering physical and mechanical properties. Highly unsaturated polymers such as polyisoprene are easily modified because the olefinic bond is readily available. Their high reactivity with a variety of chemical substances offers advantages in chemical modification and vulcanization. However, reaction with oxygen and ozone causes degradation and loss of physical and mechanical properties. Synthetic polyisoprene is processed on conventional rubber machinery. Compounding technology is similar to that used for natural rubber. Typical formulations are given. A brief discussion of isoprene copolymers and 1,4‐ trans ‐polyisoprene is included. Isoprene is classified as a flammable liquid. It is a moderate irritant to the skin, eyes, and mucous membranes. The primary use for cis ‐1,4‐polyisoprene is in tires and tire products. It is also used, eg, in molded and mechanical goods, adhesives, belts, foam rubber, and elastic threads.. Automotive molded products and medical applications are typical. Trans ‐1,4‐Poyisoprene can be extracted, calendered, injection molded, and compression molded. It can be used in blends with other polymers. Its main use is in golf ball covers.

show abstract

The synthesis and catalytic activity of polymeric compounds containing alkali metals

Cited by 2 publications

References 3 publications

Synthetic Polyisoprene Rubber as a Mimic of Natural Rubber: Recent Advances on Synthesis, Nanocomposites, and Applications

Synthetic Polyisoprene Rubber as a Mimic of Natural Rubber: Recent Advances on Synthesis, Nanocomposites, and Applications

Isoprene Polymers

Contact Info

Product

Resources

About