Polymers

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9 pages, 2926 KiB

Open AccessArticle

Synthesis and Characterization of Bipyridine-Based Polyaminal Network for CO₂ Capture

by Nazeeha S. Alkayal, Maha M. Alotaibi, Nada Y. Tashkandi and Maymounah A. Alrayyani

Polymers 2022, 14(18), 3746; https://doi.org/10.3390/polym14183746 - 07 Sep 2022

Cited by 1 | Viewed by 1486

Abstract

The response to the high demand for decreasing the amount of CO₂ in the atmosphere, a new polyaminal-based polymer network was designed and successfully prepared through one-pot polycondensation reaction of melamine and [2,2′-Bipyridine]-5,5′-dicarbaldehyde. The formation of the polymer structure was confirmed by [...] Read more.

The response to the high demand for decreasing the amount of CO₂ in the atmosphere, a new polyaminal-based polymer network was designed and successfully prepared through one-pot polycondensation reaction of melamine and [2,2′-Bipyridine]-5,5′-dicarbaldehyde. The formation of the polymer structure was confirmed by FT-IR, solid-state ¹³C NMR, and powder-X-ray diffraction. The porous properties of the polymeric structure were confirmed by field-emission scanning electron microscope and N₂ adsorption–desorption methods at 77 K. The prepared polymer can take up 1.02 mmol/g and 0.71 mmol/g CO₂ at 273 K and 298 K, respectively, despite its relatively modest Brunauer–Emmett–Teller (BET) surface area (160.7 m²/g), due to the existence of superabundant polar groups on the pore surfaces. Full article

(This article belongs to the Special Issue Advances in Functional Polymeric Materials: Applications in Applied Technologies)

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15 pages, 3313 KiB

Open AccessArticle

Synthesis and Application of Reactive Acrylic Latexes: Effect of Particle Morphology

by Catalina N. Cheaburu-Yilmaz, Cigdem Kilicarislan Ozkan and Onur Yilmaz

Polymers 2022, 14(11), 2187; https://doi.org/10.3390/polym14112187 - 27 May 2022

Cited by 7 | Viewed by 2141

Abstract

The aim of the study is the synthesis and characterization of epoxy functional reactive polyacrylic latexes, e.g., poly (BA-co-MMA-co-AN-co-GMA) with core/shell and non-structured (random) particle morphologies. Additionally, their performance as binders and coating ability in leather finishing were studied. The epoxy functional polymers [...] Read more.

The aim of the study is the synthesis and characterization of epoxy functional reactive polyacrylic latexes, e.g., poly (BA-co-MMA-co-AN-co-GMA) with core/shell and non-structured (random) particle morphologies. Additionally, their performance as binders and coating ability in leather finishing were studied. The epoxy functional polymers were synthesized via the seeded emulsion polymerization technique and the obtained latexes were characterized by means of particle size, zeta potential, FTIR, TEM, DSC, DMTA, and TGA. The results showed that the particle size and zeta potential values were very similar for both latexes, except core/shell latex had slightly higher particle size. DSC, TEM, and DMTA studies verified the successful synthesis of core/shell latex morphology. The copolymer films were elastic in nature and had low T_g values (−13 and −20 °C). The performance results showed some different behavior for core/shell and random copolymer coatings. The abrasion resistance of the leather finish with random copolymer as binder exhibited slightly better values, especially in wet conditions. On the other hand, the leathers finished with core/shell binder showed better performance in flexing endurance and the water spotting test. Full article

(This article belongs to the Special Issue Advances in Functional Polymeric Materials: Applications in Applied Technologies)

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18 pages, 4077 KiB

Open AccessArticle

Development and Evaluation of MCC-SiO₂/CMC-SiO₂ Conjugates as Tablet Super-Disintegrants

by Tanikan Sangnim, Simran Kaur Zandu, Sukhanpreet Kaur, Oluwatoyin A. Odeku, Kampanart Huanbutta and Inderbir Singh

Polymers 2022, 14(5), 1035; https://doi.org/10.3390/polym14051035 - 04 Mar 2022

Cited by 1 | Viewed by 2275

Abstract

In the present study, microcrystallinecellulose–colloidal silicon dioxide (MCC-SiO₂) and carboxymethylcellulose–colloidal silicon dioxide (CMC-SiO₂) conjugates have been investigated as superdisintegrants in fast dissolving tablets (FDTs). MCC-SiO₂ and CMC-SiO₂ conjugates were prepared and micromeritic studies, FTIR, SEM and XRD [...] Read more.

In the present study, microcrystallinecellulose–colloidal silicon dioxide (MCC-SiO₂) and carboxymethylcellulose–colloidal silicon dioxide (CMC-SiO₂) conjugates have been investigated as superdisintegrants in fast dissolving tablets (FDTs). MCC-SiO₂ and CMC-SiO₂ conjugates were prepared and micromeritic studies, FTIR, SEM and XRD methods were utilized for characterizing the powdered conjugates. The conjugates were used for the preparation of domperidone FDTs by direct compression and the wetting time, water absorption ratio, disintegration time and in vitro drug release were evaluated. Effective pore radius of MCC-SiO₂ and CMC-SiO₂ conjugates for 1:1, 1:2.5 and 1:5 was found to be 13.35 ± 0.31 µm, 15.66 ± 0.17 µm and 18.38 ± 0.44 µm, and 16.81 ± 0.24 µm, 20.12 ± 0.39 µm and 26.37 ± 0.24 µm, respectively, compared to 12.21 ± 0.23 µm for MCC and 13.65 ± 0.21 µm for CMC. The results of effective pore radius indicate the wicking capability as well as the disintegration potential of MCC-SiO₂ and CMC-SiO₂ conjugates over pure MCC and CMC. The results of wetting time, water absorption ratio and disintegration time for MCC-SiO₂ conjugates were found to be in the range of 19 ± 1.21 to 30 ± 1.33 s, 42 ± 0.28 to 49 ± 0.47% and 15 ± 2 to 40 ± 1 s, and for CMC-SiO₂ conjugates were found to be in the range of 21 ± 1.13 to 40 ± 1.17 s, 42 ± 0.94 to 49 ± 0.57% and 12 ± 2 to 20 ± 3 s, respectively. Conjugation of MCC and CMC with SiO₂ led to the formation of a complex with remarkable tablet superdisintegrant potential that could be used in preparing fast disintegrating tablets. Full article

(This article belongs to the Special Issue Advances in Functional Polymeric Materials: Applications in Applied Technologies)

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12 pages, 3804 KiB

Open AccessArticle

Glycidate as a High-Strength Epoxy Adhesive Curable with Amine under Ambient Conditions

by Bungo Ochiai and Katsutaka Soegawa

Polymers 2022, 14(5), 957; https://doi.org/10.3390/polym14050957 - 27 Feb 2022

Cited by 2 | Viewed by 2161

Abstract

This paper reports that glycidates bearing epoxy moieties with adjacent ester can be cured with diethylenetriamine (DETA) under mild conditions and exhibit high adhesiveness. Curing of bifunctional glycidates with DETA gave cross-linked products. The curing started at a lower temperature (7 °C) than [...] Read more.

This paper reports that glycidates bearing epoxy moieties with adjacent ester can be cured with diethylenetriamine (DETA) under mild conditions and exhibit high adhesiveness. Curing of bifunctional glycidates with DETA gave cross-linked products. The curing started at a lower temperature (7 °C) than the analogous glycidyl ether (27 °C), while the rate of the curing was slower due to the lower activation energy (E_a = 57 kJ/g) and exothermicity (ΔH = 58 J/g) as confirmed by DSC analysis. The curing system of neopentyl glycol diglycidate and DETA effectively adhered aluminum plates by curing at 25 °C, and the strength was more than five times higher than the curing with analogous glycidyl ether. The higher adhesive strength under curing of ambient conditions and facile preparation of monomers are the significant advantages of this curing. Full article

(This article belongs to the Special Issue Advances in Functional Polymeric Materials: Applications in Applied Technologies)

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16 pages, 7683 KiB

Open AccessArticle

Defining Swelling Kinetics in Block Copolymer Thin Films: The Critical Role of Temperature and Vapour Pressure Ramp

by Sudhakara Naidu Neppalli, Timothy W. Collins, Zahra Gholamvand, Cian Cummins, Michael A. Morris and Parvaneh Mokarian-Tabari

Polymers 2021, 13(23), 4238; https://doi.org/10.3390/polym13234238 - 03 Dec 2021

Viewed by 1679

Abstract

We studied the kinetics of swelling in high-χ lamellar-forming poly(styrene)-block- poly(lactic acid) (PS-b-PLA) block copolymer (BCP) by varying the heating rate and monitoring the solvent vapour pressure and the substrate temperature in situ during solvo-thermal vapour annealing (STVA) in [...] Read more.

We studied the kinetics of swelling in high-χ lamellar-forming poly(styrene)-block- poly(lactic acid) (PS-b-PLA) block copolymer (BCP) by varying the heating rate and monitoring the solvent vapour pressure and the substrate temperature in situ during solvo-thermal vapour annealing (STVA) in an oven, and analysing the resulting morphology. Our results demonstrate that there is not only a solvent vapour pressure threshold (120 kPa), but also that the rate of reaching this pressure threshold has a significant effect on the microphase separation and the resulting morphologies. To study the heating rate effect, identical films were annealed in a tetrahydrofuran (THF) vapour environment under three different ramp regimes, low

(r_{T} < 1 ° C / \min

), medium

(2 < r_{T} < 3 ° C / \min)

and high

(r_{T} > 4 ° C / \min)

, for 60, 90 and 120 min, respectively, while the solvent vapour pressure and the substrate temperature were measured in real time. The translational order improved significantly with increasing the heating rate. The solvent mass uptake calculated for the different ramp regimes during annealing is linearly proportional to time, indicating that the swelling kinetics followed Case II diffusion. Two stages of the swelling behaviour were observed: (i) diffusion at the initial stages of swelling and (ii) stress relaxation, controlled at later stages. Films with a faster rate of increase in vapour pressure

(r_{P} > 2 kPa / \min

) reached the pressure threshold value at an early stage of the swelling and attained a good phase separation. According to our results, highly ordered patterns are only obtained when the volume fraction of the solvent exceeds the polymer volume fraction, i.e.,

(φ_{s} \geq φ_{p})

_, during the swelling process, and below this threshold value

(φ_{s} = 0.5)

, the films did not obtain a good structural order, even at longer annealing times. Full article

(This article belongs to the Special Issue Advances in Functional Polymeric Materials: Applications in Applied Technologies)

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12 pages, 3162 KiB

Open AccessArticle

Effect of Glycerol on an N-Vinylpyrrolidone-Based Photopolymer for Transmission Holography

by Huishi Pi, Weiping Li, Zhiwei Shi, Haining Chen and Xiaoyu Jiang

Polymers 2021, 13(11), 1754; https://doi.org/10.3390/polym13111754 - 27 May 2021

Cited by 1 | Viewed by 2116

Abstract

N-vinylpyrrolidone (NVP) has a large molecular structure, so it is difficult to diffuse during holographic recording, especially at low spatial frequencies. We used glycerol to promote the diffusion of NVP, and successfully improved the holographic performance of the photopolymer at low spatial frequencies. [...] Read more.

N-vinylpyrrolidone (NVP) has a large molecular structure, so it is difficult to diffuse during holographic recording, especially at low spatial frequencies. We used glycerol to promote the diffusion of NVP, and successfully improved the holographic performance of the photopolymer at low spatial frequencies. As the concentration of glycerol increases, the holographic performance first increases and then remains stable. The optimal concentration of glycerol is 0.21 mol/L. At this concentration, the maximum diffraction efficiency of the photopolymer is 84%, the refractive index modulation is 1.95 × 10⁻³, and the photosensitive sensitivity is 7.91 × 10⁻⁴ cm²/mJ. Compared with the control group, the maximum diffraction efficiency, maximum refractive index modulation and photosensitivity at low spatial frequencies (800 lp/mm) have increased by 11.19 times, 4.69 times and 1.71 times, respectively. Using the optimized photopolymer for transmission holographic recording and reproduction, we have obtained a clear and bright transmission hologram. The photopolymer modified with glycerol is expected to be applied to the fields of holography, diffractive optics, and so on. Full article

(This article belongs to the Special Issue Advances in Functional Polymeric Materials: Applications in Applied Technologies)

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19 pages, 4653 KiB

Open AccessEditor’s ChoiceArticle

New Approach for Preparing In Vitro Bioactive Scaffold Consisted of Ag-Doped Hydroxyapatite + Polyvinyltrimethoxysilane

by Marzieh Rabiei, Arvydas Palevicius, Reza Ebrahimi-Kahrizsangi, Sohrab Nasiri, Andrius Vilkauskas and Giedrius Janusas

Polymers 2021, 13(11), 1695; https://doi.org/10.3390/polym13111695 - 22 May 2021

Cited by 12 | Viewed by 2231

Abstract

Recently, researchers have focused on the biocompatibility and mechanical properties of highly porous structures of biomaterials products. Porous composites are a new category of bioengineering that possess excellent functional and structural properties. In this study, the physical and mechanical properties of prepared doped [...] Read more.

Recently, researchers have focused on the biocompatibility and mechanical properties of highly porous structures of biomaterials products. Porous composites are a new category of bioengineering that possess excellent functional and structural properties. In this study, the physical and mechanical properties of prepared doped silver (Ag)-hydroxyapatite (HA) by the mechanochemical and spark plasma sintering (SPS) methods were investigated. The influence of dopant on phase formation, structural properties, mechanical properties and morphological characteristics was investigated. Furthermore, in this case, as a new approach to produce a porous scaffold with an average size of >100 µm, the hair band was used as a mold. According to the Monshi–Scherrer method, the crystal size of scaffold was calculated 38 ± 2 nm and this value was in the good agreement with average value from transmission electron microscopy (TEM) analysis. In addition, the stress–strain compression test of scaffold was considered, and the maximum value of compressive strength was recorded ~15.71 MPa. Taking into account the XRD, TEM, Fourier-transform infrared (FTIR), scanning electron microscope (SEM) and energy dispersive X-Ray analysis (EDAX) analysis, the prepared scaffold was bioactive and the effects of doped Ag-HA and the use of polyvinyltrimethoxysilane (PVTMS) as an additive were desirable. The results showed that the effect of thermal treatment on composed of Ag and HA were impressive while no change in transformation was observed at 850 °C. In addition, PVTMS plays an important role as an additive for preventing the decomposition and creating open-microporous in the scaffold that these porosities can be helpful for increasing bioactivity. Full article

(This article belongs to the Special Issue Advances in Functional Polymeric Materials: Applications in Applied Technologies)

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Review

Jump to: Research

27 pages, 4625 KiB

Open AccessReview

Recent Developments in Artificial Super-Wettable Surfaces Based on Bioinspired Polymeric Materials for Biomedical Applications

by Ansar Abbas, Chen Zhang, Muhammad Asad, Ahsan Waqas, Asma Khatoon, Sameer Hussain and Sajjad Husain Mir

Polymers 2022, 14(2), 238; https://doi.org/10.3390/polym14020238 - 07 Jan 2022

Cited by 15 | Viewed by 3441

Abstract

Inspired by nature, significant research efforts have been made to discover the diverse range of biomaterials for various biomedical applications such as drug development, disease diagnosis, biomedical testing, therapy, etc. Polymers as bioinspired materials with extreme wettable properties, such as superhydrophilic and superhydrophobic [...] Read more.

Inspired by nature, significant research efforts have been made to discover the diverse range of biomaterials for various biomedical applications such as drug development, disease diagnosis, biomedical testing, therapy, etc. Polymers as bioinspired materials with extreme wettable properties, such as superhydrophilic and superhydrophobic surfaces, have received considerable interest in the past due to their multiple applications in anti-fogging, anti-icing, self-cleaning, oil–water separation, biosensing, and effective transportation of water. Apart from the numerous technological applications for extreme wetting and self-cleaning products, recently, super-wettable surfaces based on polymeric materials have also emerged as excellent candidates in studying biological processes. In this review, we systematically illustrate the designing and processing of artificial, super-wettable surfaces by using different polymeric materials for a variety of biomedical applications including tissue engineering, drug/gene delivery, molecular recognition, and diagnosis. Special attention has been paid to applications concerning the identification, control, and analysis of exceedingly small molecular amounts and applications permitting high cell and biomaterial cell screening. Current outlook and future prospects are also provided. Full article

(This article belongs to the Special Issue Advances in Functional Polymeric Materials: Applications in Applied Technologies)

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