Swelling and Mechanical Properties of Solution-Crosslinked Poly(isobutylene) Gels

Durmaz, Selda; Fank, Sinan; Okay, Oğuz

doi:10.1002/1521-3935(20020301)203:4<663::aid-macp663>3.0.co;2-w

Cited by 10 publications

(10 citation statements)

References 11 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…where ϕ 2 is the volume fraction of IIR/PC18A in its equilibrium swollen state in toluene, χ is the polymer−solvent interaction parameter, given by χ = 0.49 + 0.25 ϕ 2 for the IIR- toluene system in the range of ϕ 2 between 0.01 and 0.10, 77 and V 1 is the molar volume of toluene (106 mL•mol −1 ). The volume fraction ϕ 2 was calculated from the equilibrium weight swelling ratio q w using ϕ 2 = d 1 /(ρq w ) where ρ are d 1 are the densities of IIR (0.92 g•mL −1 ) 77 and toluene (0.867 g•mL −1 ), respectively.…”

Section: Resultsmentioning

confidence: 99%

“…Moreover, because the crystalline domains and hydrophobic associations completely dissociate in good solvents such as toluene, ,,, it is likely that the swollen c-IPNs containing around 95% toluene only have chemical cross-links. The density of chemical cross-links ν e,chem was estimated from both the equilibrium swelling ratio q w and Young’s modulus E (=3 G ) of the swollen c-IPNs using the equations where ϕ 2 is the volume fraction of IIR/PC18A in its equilibrium swollen state in toluene, χ is the polymer–solvent interaction parameter, given by χ = 0.49 + 0.25 ϕ 2 for the IIR-toluene system in the range of ϕ 2 between 0.01 and 0.10, and V 1 is the molar volume of toluene (106 mL·mol –1 ). The volume fraction ϕ 2 was calculated from the equilibrium weight swelling ratio q w using ϕ 2 = d 1 /(ρ q w ) where ρ are d 1 are the densities of IIR (0.92 g·mL –1 ) and toluene (0.867 g·mL –1 ), respectively.…”

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

Solvent-Free UV Polymerization of n-Octadecyl Acrylate in Butyl Rubber: A Simple Way to Produce Tough and Smart Polymeric Materials at Ambient Temperature

Bilici

Bayazit

et al. 2021

ACS Appl. Mater. Interfaces

Self Cite

View full text Add to dashboard Cite

One of the most fascinating challenges in recent years has been to produce mechanically robust and tough polymers with smart functions such as self-healing and shape-memory behavior. Here, we report a simple and versatile strategy for the preparation of a highly tough and highly stretchable interconnected interpenetrating polymer network (c-IPN) based on butyl rubber (IIR) and poly(n-octadecyl acrylate) (PC18A) with thermally induced healing and shape-memory functions. Solventfree UV polymerization of n-octadecyl acrylate (C18A) at 30 ± 2 °C in the presence of IIR leads to IIR/PC18A c-IPNs with seaisland or co-continuous morphologies depending on their IIR contents. The lamellar crystals with a melting temperature T m of 51−52 °C formed by side-by-side packed octadecyl (C18) side chains are responsible for more than 99% of effective cross-links in c-IPNs, the rest being hydrophobic associations and chemical cross-links. The c-IPNs exhibit varying stiffness (9−34 MPa), stretchability (72−740%), and a significantly higher toughness (1.9− 12 MJ•m −3 ) than their components, which can be tuned by changing the IIR/PC18A weight ratio. The properties of c-IPNs could also be tuned by incorporating a second, noncrystallizable hydrophobic monomer, namely, lauryl methacrylate (C12M), in the melt mixture. We show that the lamellar clusters acting as sacrificial bonds break at the yield point by dissipation of energy, while the ductile amorphous continuous phase keeps the structure together, leading to the toughness improvement of c-IPNs. They exhibit a two-step healing process with >90% healing efficiency with respect to the modulus and a complete shape-recovery ratio induced by heating above T m of alkyl crystals. The temperature-induced healing occurs via a quick step where C18 bridges form between the damaged surfaces followed by a slow step controlled by the interdiffusion of C18A segments in the bulk. We also show that the strategy developed here is suitable for a variety of rubbers and n-alkyl (meth)acrylates of various side-chain lengths.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

Solvent-Free UV Polymerization of n-Octadecyl Acrylate in Butyl Rubber: A Simple Way to Produce Tough and Smart Polymeric Materials at Ambient Temperature

Bilici

Bayazit

et al. 2021

ACS Appl. Mater. Interfaces

Self Cite

View full text Add to dashboard Cite

show abstract

“…Swelling in deionized water gives place to neutral PVI gels and, as shown in Figure 1, the elastic modulus scarcely changes with respect to the corresponding as‐synthesized sample. The elastic modulus of polyelectrolyte gels has received great attention 11, 13, 15, 41–47. Here, three types of ionic gels were studied, (i) the highly charged PSS polyelectrolyte gel (Fig.…”

Section: Resultsmentioning

confidence: 99%

“…The formation of ionic crosslinks or intermolecular salt‐linkages seems to dominate the hardness of some amphoteric gels47 but that is not the case for PVI‐SS, as shown below. Overshootings may be due to several phenomena, for example, to post‐crosslinking reactions taking place during swelling; in such case, overshooting is usually accompanied by an enlargement of G 46. However, if the overshooting is associated with the loss of mechanical integrity caused by removal of weakly crosslinked material during a prolonged immersion, G is reduced 10.…”

Section: Resultsmentioning

confidence: 99%

Compression elastic modulus of neutral, ionic, and amphoteric hydrogels based on N‐vinylimidazole

Valencia¹,

Baselga²,

Piérola³

2009

J Polym Sci B Polym Phys

View full text Add to dashboard Cite

Several hydrogels of N-vinylimidazole and sodium styrenesulfonate have been prepared by radical cross-linking copolymerization in aqueous solution, using N,N 0 -methylene-bisacrylamide as crosslinker. Depending on composition, these hydrogels were neutral, amphoteric, cationic or anionic. Compression-strain measure-ments were performed on samples as-synthesized and swollen in deionized water or in acid aqueous solutions, with and without salt. It was thus found that the cross-linking densities determined by compression measurements on assynthesized sam-ples are in good accordance with those calculated by means of the model of polymer networks with pendant vinyl groups. A non-Gaussian parameter (b) was introduced to explain that the elastic moduli (G) of samples swollen at equilibrium are larger than predicted by the Gaussian model. The b values of the neutral or ionized systems increase with swelling and fall into a single curve, which denotes a common behav-ior. Swelling has two opposite effects on G; on the one hand G decreases because the polymer volume fraction diminish and the system shifts from the affine limit to the phantom one; on the other, b increases and contributes to increasing G. The balance of those two opposite effects determines the variation of G with swelling. The possi-ble contribution of ionic crosslinks to m e for the polyampholyte and for the polycation wearing divalent counteranions was discussed.A peculiar system is poly(sodium styrenesulfonate), whose cross-linking density is much lower than expected.

show abstract

“…The samples were immersed in pure toluene at room temperature for two days to allow the swelling to reach diffusion equilibrium. Then, the test pieces were taken out and the adhered liquid was rapidly removed by blotting with filter paper [16,17]. The swelling ratio was estimated according to the equation where, m 0 is the weight of test piece before swelling and m t is the weight of the swelling test piece after time t of immersion.…”

Section: Swelling Testmentioning

confidence: 99%

Thermo-Mechanical Degradation for Hard Barium Ferrite- Natural Rubber Composites

Makled

2018

Egypt. J. Physics

View full text Add to dashboard Cite

T HE aim of this work is to evaluate the thermal stability of the natural rubber-hard barium ferrite composites at different contents of ferrite particles. The tensile, hardness and swelling were tested before and after ageing for 15, 30 and 45 days at 80 o C. The composites were prepared by two roll mixing method. In this study the composites vulcanizes were cured up to respective cure time of each sample. Then aged for different periods for mechanical characterization. SEM images indicate no aggregation of the ferrite particles before and after mixing with rubber. Thermal stability of the composites during the first 2 weeks is noticed. After 15 days of aging, all the mechanical parameters decreased drastically with increasing aging time up to 30 days. The FTIR reflects the thermal stability of the composites. A Swelling test showed the higher thermal stability and the optimum vulcanization parameter of the composites.For all samples, the thermal degradation increased after 15 days

show abstract

Swelling and Mechanical Properties of Solution-Crosslinked Poly(isobutylene) Gels

Cited by 10 publications

References 11 publications

Solvent-Free UV Polymerization of n-Octadecyl Acrylate in Butyl Rubber: A Simple Way to Produce Tough and Smart Polymeric Materials at Ambient Temperature

Solvent-Free UV Polymerization of n-Octadecyl Acrylate in Butyl Rubber: A Simple Way to Produce Tough and Smart Polymeric Materials at Ambient Temperature

Compression elastic modulus of neutral, ionic, and amphoteric hydrogels based on N‐vinylimidazole

Thermo-Mechanical Degradation for Hard Barium Ferrite- Natural Rubber Composites

Contact Info

Product

Resources

About