The chemistry of novolac resins: 3. 13C and 15N n.m.r. studies of curing with hexamethylenetetramine

Zhang, Xiaoqing; Looney, Mark G.; Solomon, David H.; Whittaker, Andrew K.

doi:10.1016/s0032-3861(97)00141-9

Cited by 119 publications

(95 citation statements)

References 23 publications

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“…3a also reveals that the peaks of C-H stretching vibration (2800-3200 cm -1 ) and C-O stretching (1030 cm -1 ) are becoming more pronounced as a function of increasing vacuum time. This strongly suggests that the use of vacuum further assisted in the polycondensation of phenol oligomers, which resulted in resin crosslinking [45][46][47]. This vacuum-assisted reaction is most likely due to the faster drying rates, which leads to increased resin concentration.…”

Section: Materials Characterisationmentioning

confidence: 99%

Vacuum-assisted tailoring of pore structures of phenolic resin derived carbon membranes

Jalil

Wang²,

Yacou

et al. 2017

Journal of Membrane Science

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This work shows the preparation and separation performance assessment of carbon membranes derived from phenolic resin by a vacuum-assisted method and carbonisation in an inert atmosphere.The vacuum time played an important role in tailoring the structure of the membranes. For instance, pore volumes and surface areas increased from 0.81 and 834 to 2.2 cm 3 g -1 and 1910 m 2 g -1 , respectively, as the vacuum time exposure increased from 0 to 1200 s. The significant structural changes correlated very well with water permeation, as fluxes increased by 91% as the vacuum time increased from 0 to 1200s, reaching up to 169 kg m -2 h -1 at 5 bar. Molecular weight cut-off tests showed no rejection for the smaller glucose and sucrose molecules, though this increased to ~ 80% and full rejection for 36kD and 400kD polyvinyl pyrrolidine. Interestingly, FTIR spectra showed that the peaks of C-H stretching vibration (2800-3200 cm -1 ) and C-O stretching (1030 cm -1 ) became more pronounced as a function of increasing vacuum time, strongly suggesting that the use of vacuum further assisted in the polycondensation of phenolic oligomers. Based on these outcomes, a cluster to cluster model is proposed, whereby vacuum application promoted crosslinking reactions of the phenolic resin, creating microporous regions within the clusters, and mesoporous regions between the clusters. 2 Graphical AbstractKeywords: carbon membranes; vacuum-assisted method; water; molecular weight cut-off.

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Section: Materials Characterisationmentioning

confidence: 99%

Vacuum-assisted tailoring of pore structures of phenolic resin derived carbon membranes

Jalil

Wang²,

Yacou

et al. 2017

Journal of Membrane Science

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“…Hydrogen bonded adducts with phenols 55,56 and salts with acids are also known 57 . 13 C-labelled or 15 N-labelled derivatives of HMTA have been synthesized 58 together with 13 C-and 15 N-labelled HMTA 59 .…”

Section: Hexamethylenetetramine (Hmta)mentioning

confidence: 99%

“…The aldehyde groups and perhaps even carboxyl groups also form in the oxidation. The various proposed reaction intermediates are outlined in Scheme 12 59,73 .…”

Section: Chemistry Of Crosslinking Reactions Involving Hmtamentioning

confidence: 99%

Polymers Based on Phenols

Solomon¹,

Qiao²,

Caulfield³

2003

PATAI'S Chemistry of Functional Groups

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“…11 Although the high potential of such hybrid materials is becoming more and more obvious, there have been very few efforts directed toward preparing inorganic-organic hybrids. On the other hand, phenol-formaldehyde resins have been well known for 100 years 12,13 because of their low cost, aging resistance, dimensional stability, and high tensile strength, so they are used in many applications ranging from molding compounds and laminates, to adhesives, etc.…”

Section: Introductionmentioning

confidence: 99%

Preparation and characterization of SiO₂‐functionalized phenolic resin hybrid materials

Hernández‐Padrón¹,

Lima²,

Nava³

et al. 2002

Adv Polym Technol

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ABSTRACT:The preparation and characterization of a hybrid material produced by the combination of a modified aldehydic-phenolic resin (MPR) of the Novolac-type with an inorganic oxide is described. Silica sols were embedded within a phenolic resin matrix of a modified Novolac-type. Functionalization of the resin with the introduction of carboxylic groups in the course of the reaction is key to rendering a strong chemical union between the silanol groups of the SiO 2 substrate and the COOH groups attached to the MPR resin, producing a core (SiO 2 )-shell (MPR) structure. The hybrid samples were characterized by spectroscopic techniques (FT-IR and

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The chemistry of novolac resins: 3. 13C and 15N n.m.r. studies of curing with hexamethylenetetramine

Cited by 119 publications

References 23 publications

Vacuum-assisted tailoring of pore structures of phenolic resin derived carbon membranes

Vacuum-assisted tailoring of pore structures of phenolic resin derived carbon membranes

Polymers Based on Phenols

Preparation and characterization of SiO₂‐functionalized phenolic resin hybrid materials

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The chemistry of novolac resins: 3. 13C and 15N n.m.r. studies of curing with hexamethylenetetramine

Cited by 119 publications

References 23 publications

Vacuum-assisted tailoring of pore structures of phenolic resin derived carbon membranes

Vacuum-assisted tailoring of pore structures of phenolic resin derived carbon membranes

Polymers Based on Phenols

Preparation and characterization of SiO2‐functionalized phenolic resin hybrid materials

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Product

Resources

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Preparation and characterization of SiO₂‐functionalized phenolic resin hybrid materials