Studies on natural rubber bound para ‐phenylenediamine antioxidants in NBR

2006

ABSTRACT:The synthesis of N-(4-aminodiphenylmethane) acrylamide (ADPMA) was performed through the reaction of 4,4Ј-diaminodiphenyl methane and acryloyl chloride in the presence of triethyl amine. The grafting of AD-PMA onto natural rubber was executed with UV radiation. Benzoyl peroxide was used to initiate the free-radical grafting copolymerization. Natural rubber-graft-N-(4-aminodiphenyl methane) acrylamide (NR-g-ADPMA) was characterized with an IR technique. We studied the effect of aging on the mechanical properties and the swelling and extraction phenomena for acrylonitrile-butadiene copolymer (NBR) vulcanizates, which contained the prepared NR-g-ADPMA and a commercial antioxidant, N-isopropyl-NЈ-phenyl-pphenylenediamine. The prepared antioxidant enhanced both the mechanical properties of the NBR vulcanizates and the permanence of the ingredients in these vulcanizates.

Section: Methodsmentioning

confidence: 99%

“…The IR spectrum of NR is shown in Figure 3. The spectrum shows the characteristic peaks of the CC group at 1693.4 cm −1 , the CH 2 C(CH 3 )H group at 2924.6 cm −1 , and the CH 2 group at 1423.5 cm −1 9…”

Section: Methodsmentioning

confidence: 99%

Synthesis, characterization, and evaluation of natural rubber‐graft‐N‐(4‐aminodiphenyl methane) acrylamide as an antioxidant

2006

“…5 Figures 6 and 7 indicate that after the NBR vulcanizates were exposed to aging for 14 days, the prepared NR-g-pAP improves the mechanical properties of NBR vulcanizates more than the commercial antioxidants IPPD and 6PPD, respectively. Because the rubber part of the grafted antioxidant gets attached to nitrile rubber during sulfur vulcanization and the antioxidant becomes nonvolatile and nonextractable, 11 the commercial antioxidants IPPD and 6PPD have high thermal sensitivity. This high thermal sensitivity is due to the presence of isopropyl chain and 1,3-dimethylbutyl chain, respectively, in the molecular skeleton, and they produce the electron-donor effect on the benzene ring.…”

Section: Effect Of 6ppd Ippd and Nr-g-pap On The Mechanical Propertmentioning

confidence: 99%

Amelioration of acrylonitrile–butadiene copolymer properties using natural rubber graft p‐aminophenol

2006

A two-roll mill machine was used for the grafting of p-aminophenol (pAP) onto natural rubber (NR). The prepared NR graft p-aminphenol (NR-g-pAP) was characterized by 1 H NMR and IR spectroscopy techniques. The goal of this article is to study the effect of commercial antioxidants,, and the prepared NR-g-pAP, on the mechanical properties of acrylonitrile-butadiene (NBR) vulcanizates, the fluid compatibility of NBR vulcanizates, the hydraulic brake and clutch fluid dot, the diffusion out for NBR vulcanizate components, and the compression recovery of NBR vulcanizates. This study indicates that the NBR copolymer vulcanizate which contains the prepared NR-g-pAP has good protection against mechanical stress and the diffusion out of NBR vulcanizate components. The 6PPD and the prepared NR-g-pAP ameliorates the fluid compatibility of the oil seals, which is based on NBR as elastomer, and the hydraulic brake and clutch fluid dot.

“…The product was dried in an oven at 408C to constant weight within 24 h. The percent graft was taken as the ratio of the graft yield to the natural rubber multiplied by 100. 8 Degree of grafting ¼ ðW g =WNRÞ Â 100…”

Section: Synthesis Of Nr-graft-o-apmentioning

confidence: 99%

“…The synthesis of NR-graft-o-AP is shown in the following mechanism. 8,9 Formulation and mixing of NBR vulcanizates…”

Section: Synthesis Of Nr-graft-o-apmentioning

confidence: 99%

Study of the effect of natural rubber‐graft‐o‐aminophenol on the thermal stability and mechanical properties of nitrile rubber

Barakat

2010

The grafting copolymerization of natural rubber and o-aminophenol was carried out by using tworoll mill machine. The prepared grafted antioxidant, NRgraft-o-AP, analyzed by using Infrared and 1 H-NMR Spectroscopy techniques. The thermal stability, mechanical properties, and ultrasonic attenuation coefficient were evaluated for NBR vulcanizates containing the commercial antioxidant, PBN, and the prepared grafted antioxidant, NR-graft-o-AP, and the control vulcanizate. Results of the thermal stability indicate that the prepared NR-graft-o-AP can protect NBR vulcanizate against thermal treatment much better than the commercial antioxidant, PBN, and control mix, respectively. The prepared grafted antioxidant improves the mechanical properties of NBR vulcanizate.