A structural study of epoxidized natural rubber (ENR‐50) ring opening under mild acidic condition

Hamzah, R.; Bakar, Mohamad Abu; Dahham, Omar S.; Noriman, N. Z.; Dahham, Saad Sabbar

doi:10.1002/app.44123

Cited by 55 publications

(20 citation statements)

References 37 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…It is noted that the ENR was prepared by chemically modifying NR, by adding epoxide groups. Therefore, ENR possesses relatively high polarity in its molecular structure and can self‐cross‐link at the opened oxirane rings and by hydrogen bonds or polar interactions, either within one molecule or between neighboring ENR molecules …”

Section: Resultsmentioning

confidence: 99%

“…Therefore, ENR possesses relatively high polarity in its molecular structure and can self-cross-link at the opened oxirane rings and by hydrogen bonds or polar interactions, either within one molecule or between neighboring ENR molecules. 22,[45][46][47] 3.4 | Dynamic mechanical analysis Figure 6 shows the DMA thermograms with storage modulus (E′) and tan δ as functions of temperature, for the parent polymers (PBS, NR, ENR-25, and ENR-50) and the NR/PBS simple blends with various types of NR, at the fixed blend proportions rubber/PBS = 60/ 40 wt%. It can be seen that the storage modulus shows three distinct regions: a glassy high modulus region where the segmental mobility is restricted, a transition region with substantial decrease in E′ as temperature increases, and a rubbery region with increasing chain mobility and drastic loss of modulus with increasing temperature.…”

Section: Morphological Propertiesmentioning

confidence: 99%

See 1 more Smart Citation

Influence type of natural rubber on properties of green biodegradable thermoplastic natural rubber based on poly(butylene succinate)

Faibunchan

Pichaiyut

Chueangchayaphan

et al. 2019

Polymers for Advanced Techs

View full text Add to dashboard Cite

Green biodegradable thermoplastic natural rubber (GB‐TPNR) based on simple blend of natural rubber (NR) and poly(butylene succinate) (PBS) was prepared using three NR alternatives: unmodified NR and epoxidized NR with 25‐ or 50‐mol% epoxide (ie, ENR‐25 or ENR‐50). It was found that ENR‐50/PBS blend showed the best compatibility, which resulted in superior mechanical and thermal properties with the highest crystallinity of the PBS phase, on comparing with the ENR‐25/PBS and NR/PBS blends. This might be attributed to stronger chemical interactions between the epoxide groups in ENR‐50 and the polar functional groups in PBS, which were confirmed by Fourier transform infrared (FTIR). Furthermore, scanning electron microscopy (SEM), atomic force microscopy (AFM), and polarizing optical microscopy (POM) micrographs of ENR‐50/PBS blend revealed phase separation with finer‐grained cocontinuous structure than in ENR‐25/PBS and NR/PBS simple blends. Furthermore, the chemical interactions in ENR‐50/PBS blend enhanced the resistance to accelerated weathering.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Morphological Propertiesmentioning

confidence: 99%

Influence type of natural rubber on properties of green biodegradable thermoplastic natural rubber based on poly(butylene succinate)

Faibunchan

Pichaiyut

Chueangchayaphan

et al. 2019

Polymers for Advanced Techs

View full text Add to dashboard Cite

show abstract

“…Cure extent values of epoxy silane containing compounds are lower when compared to their equivalent amino silane compounds. This was explained with that epoxy groups could not complete ring‐opening reaction without any acid catalyst in the present vulcanization media 31,32 . These compounds also exhibit larger scorch time value indicating late initiation of vulcanization.…”

Section: Resultsmentioning

confidence: 80%

“…This was explained with that epoxy groups could not complete ring-opening reaction without any acid catalyst in the present vulcanization media. 31,32 These compounds also exhibit larger scorch time value indicating late initiation of vulcanization. One other important parameter to characterize rubber vulcanization reaction is cure rate index.…”

Section: Rheological Propertiesmentioning

confidence: 99%

Vulcanization of chlorinated polyethylene / chloroprene rubber compounds at lower temperatures in the presence of reactive silanes

Ünügül

Karaağaç

2021

J of Applied Polymer Sci

View full text Add to dashboard Cite

Vulcanization at lower temperatures can be considered as a good alternative to reduce both investment and operation costs for cable insulation sheat and special purpose hose production lines. In this study, silane vulcanization of chlorinated polyethylene and chloroprene rubber blends at lower temperature was investigated. Rubber compounds were prepared by using internal mixer instead of an extrusion system which is widespread used for projected applications. Rheological and dynamic properties of the rubber compounds were studied. After vulcanization, physico‐mechanical, thermal, morphological and temperature scanning stress‐relaxation properties were investigated before and after thermal aging. Structural analysis was performed by using Fourier transform infrared spectroscopy and X‐ray photoelectron spectroscopy so as to identify vulcanization reaction mechanism. All the compound compositions could be vulcanized at 110°C in the presence of water. Amino silane was found to be more effective than epoxy silane.

show abstract

“…

…”

mentioning

confidence: 99%

Preparation and stress-strain behavior of in-situ epoxidized natural rubber/SiO2 hybrid through a sol-gel method

Li¹,

Xu²,

Jia³

et al. 2018

Express Polym. Lett.

View full text Add to dashboard Cite

Epoxidized natural rubber (ENR) is derived from the partial epoxidation of the natural rubber possessing some new properties such as good wet grip, oil resistance, excellent flexibility and low rolling resistance [1,2]. The epoxy group of ENR is unstable that could be utilized for the modification of ENR or being a compatilizer [3,4] in rubber composites. It is well known that SiO 2 is used widely in industry except for carbon black, usually as a reinforcement agent or a functionalized filler to impart specific properties for rubber compounds [5]. In our previous work, The ENR/SiO 2 hybrids prepared by an openmill mixing method had been reported, and the interfacial interaction of ENR and SiO 2 was investigated. The results indicated that the ring-opening reaction of the epoxy groups of ENR chains occurs and the covalent bonds between C-OH of ENR and Si-OH groups on the silica surfaces were formed, which can improve the dispersion of silica in the rubber matrix and enhance the interfacial combination between rubber and silica. However, the hybrid obtained a good strength only with a high content of SiO 2 [6], where the elongation at break of hybrid was limited regrettably. This might be attributed to the insufficient filler-rubber interactions. There are still improvements that need to be made in the elongation at break and processability. Mark and Pan [7] firstly proposed a new approach for preparing silica-filled elastomers by generating the silica particles inside the crosslinked silicone rubber. The sol-gel process brings a good dispersion of the silica filling into the rubbery matrix. In general, the sol-gel reaction of tetraethoxysilane (TEOS) takes place easily and proceeds in the two steps, hydrolysis and condensation reactions, to produce SiO 2 . 180Preparation and stress-strain behavior of in-situ epoxidized natural rubber/SiO 2 hybrid through a sol-gel method Abstract. In this paper, epoxidized natural rubber was reinforced by silica generated in-situ though the sol-gel method using tetraethoxysilane(TEOS) as precursor. The results showed that the ring opening reaction of epoxy group appeared in the insitu reaction progress, where the hydrogen bond between Si-OH and C-OH was mainly formed to enhance the stress-strain behavior of ESH simultaneously. During the hot pressing progress, the compound was crosslinked via the chemical reaction of Si-OH and C-OH. The chemical bond between Si-OH and C-OH reinforced rubber-filler interaction, resulting further improved the stress-strain behavior. Besides, comparing with precipitated SiO 2 filled ENR, the dispersion of SiO 2 in ENR matrix was distinctly more uniform though the sol-gel method, along with the enhancement of mechanical properties. Herein, our findings open up a new way to prepare an environmentally friendly rubber composite with excellent dispersion and strong rubber-filler interaction without curing agent effectively.

show abstract

A structural study of epoxidized natural rubber (ENR‐50) ring opening under mild acidic condition

Cited by 55 publications

References 37 publications

Influence type of natural rubber on properties of green biodegradable thermoplastic natural rubber based on poly(butylene succinate)

Influence type of natural rubber on properties of green biodegradable thermoplastic natural rubber based on poly(butylene succinate)

Vulcanization of chlorinated polyethylene / chloroprene rubber compounds at lower temperatures in the presence of reactive silanes

Preparation and stress-strain behavior of in-situ epoxidized natural rubber/SiO2 hybrid through a sol-gel method

Contact Info

Product

Resources

About