化加速器和合剂在聚烯融中的化剂
Nikolaos Patsalidis1,2, George J Papakonstantopoulos3, Jan Domurath4
1Chemical and Biomolecular Engineering, University of Tennessee, Knoxville, Tennessee 37996, United States.
The journal of physical chemistry. B
|December 21, 2024
概括
了解CBS,DBTH和DPG等火山化加速器是先进弹性体的关键. DPG聚合物在聚二烯中,而CBS和DBTH则没有. 加速器强烈地结合于二氧化表面,但合剂可以取代它们.
科学领域:
- 聚合物科学与工程 聚合物科学与工程
- 材料化学 材料化学
- 计算材料科学科学 计算材料科学
背景情况:
- 化加速器的有效分散对于优化交联弹性的特性至关重要.
- 目前的弹性体配方采用复杂的混合物,其中包括用合剂功能化的粒.
研究的目的:
- 为了研究关键加速器的分子特性和自我结合行为: (N-cyclohexyl)-2-benzothiazole硫胺 (CBS),1,6-bis(N,N-dibenzylthiocarbamoyldithio) (DBTH) 和二基 (DPG) 在聚烯溶液中.
- 为了确定这些加速器对裸体和功能化表面的亲和力,考虑各种合剂,如MPTES,NXT和TESPD.
- 探索DPG在二进制DPG-CBS配方中的作用,以提高CBS溶解度.
主要方法:
- 广泛的全原子分子动力学模拟被用来研究聚烯融中的加速器行为.
- 使用自由能量计算来评估在无限稀释和有限度下加速器-基质亲和力.
- 模拟检查了与不同合剂修改的表面的相互作用,在不同的接种密度下进行模拟.
主要成果:
- CBS和DBTH在聚二烯中表现出较低的自我结合,而DPG则形成了小型联聚合物.
- 所有加速器都对表面具有很高的亲和力,DPG>CBS>DBTH.
- 合剂可以将加速器从二氧化表面移除;随着接种密度和合剂大小的增加,移位会增加.
- 在DPG-CBS混合物中,DPG充当覆盖剂,增强聚合物矩阵中的CBS可溶性.
结论:
- 火山化加速器的分子相互作用和表面亲和力显著影响弹性体网络的形成.
- 了解加速器自我关联和基板相互作用对于设计高性能化合物至关重要.
- 由于DPG能够溶解CBS,因此提供了一种改善加速器分散和弹性质的潜在策略.
相关概念视频
Polymer Classification: Stereospecificity
2.4K
Polymerization generates chiral centers along the entire backbone of a polymer chain. Accordingly, the stereochemistry of the substituent group has a significant effect on polymer properties. Polymers formed from monosubstituted alkene monomers feature chiral carbons at every alternate position in the polymer backbone. Relative to the predominant orientation of substituents at the adjacent chiral carbons, the polymer can exist in three different configurations: isotactic, syndiotactic, and...
2.4K
Accelerators
70
Accelerators in concrete serve as admixtures to speed up the hardening process, enabling the concrete to achieve early strength faster. Although accelerators do not necessarily impact the time it takes concrete to set, they reduce this time in practice. A common accelerator is calcium chloride, which is particularly useful for hastening early strength development in cold weather or for rapid repair jobs that require quick heat generation after mixing.
The effectiveness of calcium chloride can...
The effectiveness of calcium chloride can...
70
Olefin Metathesis Polymerization: Overview
2.0K
Recently, the development of olefin metathesis polymerization advanced the field of polymer synthesis. Simply put, the reorganization of substituents on their double bonds between two olefins in the presence of a catalyst is known as the olefin metathesis reaction. The use of metathesis reaction for polymer synthesis is called olefin metathesis polymerization.
Ruthenium-based Grubbs catalyst is the most commonly used catalyst for olefin metathesis polymerization. Grubbs catalyst consists...
Ruthenium-based Grubbs catalyst is the most commonly used catalyst for olefin metathesis polymerization. Grubbs catalyst consists...
2.0K
Ziegler–Natta Chain-Growth Polymerization: Overview
3.2K
Ziegler–Natta polymerization is another form of addition or chain‐growth polymerization used for synthesizing linear polymers over branched polymers. The catalyst used for polymerization is the Ziegler–Natta catalyst, named after Karl Ziegler and Giulio Natta, who developed it in 1953. This catalyst is an organometallic complex of titanium tetrachloride and triethyl aluminum, with the active form of the catalyst being an alkyl titanium compound. Using the Ziegler–Natta...
3.2K
Anionic Chain-Growth Polymerization: Overview
2.1K
The polymerization process that involves carbanion as an intermediate is called anionic polymerization. It is also a type of addition or chain-growth polymerization. Anionic polymerization gets initiated by a strong nucleophile such as an organolithium or a Grignard reagent. The most commonly used initiator for anionic polymerization is butyl lithium. Monomers involved in anionic polymerization must possess a vinyl group bonded to one or two electron-withdrawing groups. For instance,...
2.1K
Additives and Fillers in Concrete
89
Additives and fillers are integral to enhancing the properties of concrete. Pozzolans and blast-furnace slag are additives or admixtures due to their reactions with calcium hydroxide released during cement hydration. Fillers, which are finely ground and similar in fineness to Portland cement, improve concrete attributes such as workability density, and reduce capillary bleeding or cracking. Some fillers possess hydraulic properties or participate in benign reactions within the cement paste.
The...
The...
89


