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A simple and effective way was developed to prepare antibacterial poly(methyl methacrylate) (PMMA) materials from commercial PMMA and synthesized poly[2-(tert-butylamino) ethyl methacrylate] (PTBAEMA) by solution blending and solvent evaporation methods. The chemical structure of as-synthesized PTBAEMA was characterized by FTIR and 1H-NMR, and the molecular weight (Mw) and polydispersity index was determined by Gel Permeation Chromatograph. The two components, that is, PMMA and PTBAEMA, were partially miscible and of regular domain size and shape as revealed by SEM observation. Antibacterial assay revealed PMMA/PTBAEMA blends inherited the good antibacterial activity of PTBAEMA against both Staphylococcus aureus and Escherichia coli, no matter whether the bacteria were waterborne or airborne. Besides, the antibacterial performance of PMMA/PTBAEMA blends depended on the Mw and dosage of PTBAEMA, and type of bacteria strain. Furthermore, it was proved that PMMA/PTBAEMA blends killed bacteria on direct contact without releasing active component, which sufficiently met the demand of developing environment-friendly antibacterial materials. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012

Carbon aerogels were prepared by the sol-gel polymerization of petroleum pitches followed by ambient-pressure drying and then carbonization. Furfural and sulfuric acid were found to be the best crosslinking agent and best catalyst for the reaction system, respectively. It was necessary to add acetic acid as a cosolvent, and the volume ratio of toluene to acetic acid played an important role in the mass densities of the samples. The average diameters of the nanonetwork particles of the typical carbon aerogels thus obtained were about 30-40 nm, and their surface areas were over 360 m 2 /g.

Two grafted ethylene–octene copolymers [POEs; i.e., POE-g-maleic anhydried (MAH) and aminated POE (denoted by POE-g-NH2) were used as compatibilizers in immiscible blends of thermoplastic polyurethane (TPU) and POE. The effects of the compatibilizers on the dynamic rheological properties and morphologies of the TPU/POE blends were investigated. The characteristic rheological behaviors of the blends indicated that the strong interactions between the two phases were due to the compatibilization. Microstructural observation confirmed that the compatibilizers were located at the interface in the blends and formed a stable interfacial layer and smaller dispersed phase particle size. Compared with POE-g-MAH, POE-g-NH2 exhibited a better compatibilization effect in the TPU/POE blends. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008

Carbon aerogel (CA) spheres were fabricated by inverse suspension polymerization of an emulsified resorcinol–formaldehyde aqueous solution with a basic surfactant used as catalyst, and then drying by gradually heating the resultant sol–gel spheres at ambient pressure. The fabrication conditions, nanostructures of the resultant CA spheres, and their electrochemical properties were investigated. By controlling the time at which stirring started, the stirring speed, and the recipe of the emulsion solution, the diameter of the CA spheres can be controlled from 70 to 1000 μm. The internal carbon nanoparticles of the spheres are of a size ranging from 20 to 40 nm, and are interconnected into a three-dimensional network. The highest surface area and mesopore volume of the spherical CAs thus prepared reach 626 m2/g and 0.69 cm3/g, respectively. These CAs can be used as an electrode in supercapacitors, and the specific capacitance is as high as 197 F/g. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007

In this article, activated carbon aerogels (ACAs) were prepared by CO2 activation. Their pore structures were investigated by N2 adsorption–desorption analysis. ACAs have excellent microporosity (e.g. 0.36 cm3/g) and mesoporosity (e.g. 1.72 cm3/g). Adsorption characteristics of phenol, methylene blue, I2, and VB12 on ACAs in the liquid phase were studied by static adsorption experiments. Results showed that CO2 activation process is an effective way to introduce micropores in carbon aerogels, which is enhanced with the increase of activation time. As a result, the adsorption capacities of the four mentioned adsorbates on ACAs were improved gradually with the increase of activation time. However, mesopore volume is also a factor on improving adsorption properties for the relatively giant molecules methylene blue and VB12. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007

Silver-dispersed carbon aerogels (Ag/CAs) were obtained by the direct immersion of organic aerogels in aqueous AgNO3 solutions and then carbonization of the resulting material under a nitrogen atmosphere. The adsorption and antibacterial activity of Escherichia coli and Staphylococcus aureus on Ag/CAs were studied by the measurement of the amount of viable bacteria in suspensions and scanning electron microscopy (SEM) observations. The adsorbed amount of bacteria on samples without silver increased with an increase in the carbonization temperature and contact time. SEM studies showed that the adsorption capacity of Ag/CAs decreased with an increase in the silver content; this was considered to be mainly due to the dissolution behavior of bacteria by silver ions. The antibacterial test showed that 2.5 mg of Ag/CAs with more than 3.6% Ag could inhibit the growth of 105 cfu/mL E. coli in 10 mL of a Mueller–Hinton broth culture, but in the case of S. aureus, 10-mg samples just got the same antibacterial effect. An antibacterial persistency test showed that 25 mg of Ag/CAs with 6.5% Ag could kill 50 mL of 105 cfu/mL E. coli eight times. These results indicate that Ag/CAs possess strong and long-term antibacterial activity. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 1030–1037, 2006

Organic aerogels and related carbon aerogels were prepared from the NaOH-catalyzed polycondensation of resorcinol–furfural (RF) and supercritical drying in ethanol. The effect of the preparation conditions, including the RF concentration, molar ratio of resorcinol (R) to NaOH, and molar ratio of R to furfural, on the gelation time and bulk density was studied. The chemical structure of the organic aerogel was revealed by IR spectroscopy. The pyrolysis process of the organic aerogel was investigated by thermogravimetric analysis. According to characterizations of transmission electron microscopy and nitrogen adsorption, the organic and carbon aerogels we obtained had a three-dimensional network that consisted of around 30-nm particles, which defined numerous mesopores of less than 30 nm. As a result, the aerogels had high Brunauer–Emmett–Teller surface areas (698–753 m2/g) and large mesopore volumes (1.09–1.64 cm3/g). X-ray diffraction characterization indicated that the carbon aerogel was more crystalline than activated carbon but less activated than graphite. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 1429–1435, 2005

Activated carbon aerogels (ACAs) with excellent microporosity (e.g., 0.44 cm 3 /g) and mesoporosity (e.g., 1.72 cm /g) were prepared by CO 2 activation. Their structures were investigated with transmission electron microscopy and N 2 adsorption-desorption analysis. Subsequently, their adsorption properties toward organic vapors were studied with static and dynamic adsorption experiments. The micropores of the ACAs had stronger adsorption ability than those of normal porous carbons. Furthermore, the condensation of organic vapors in the mesopores of ACAs greatly enhanced their equilibrium adsorption at high relative pressures. As a result, the adsorption capacities of organic vapors on the typical ACAs prepared were about 2-3 times greater than those on normal porous carbons. In addition, they also possessed excellent adsorption dynamics and outstanding desorption and regeneration properties.

The carbon aerogels prepared by a new method through gelation and supercritical drying in isopropanol were characterized by X-ray photoelectron spectroscopy (XPS), scanning electron microscopy, and a surface area analyzer. Their chemical structure, morphology, and pore structure are discussed. We found that all of these carbon aerogel (CA-IPA) samples have almost the same carbon and oxygen elemental states, as well as similar oxygen-containing groups. The curve fitting of the C1s XPS spectra of the samples for characterizing oxygen-containing surface groups can be performed by assuming the peak type to be a Gaussian–Lorentzian Cross Product, but we cannot obtain good results using a Gaussian lineshape. When the mass density of the CA-IPA decreases, the mesopores and macropores of the samples are found to grow, but the size and the shape of individual carbon nanoparticles in various CA-IPA samples do not apparently change. The micropore volume of the CA-IPA samples increases with a decrease in the mass density, while the mesopore volume has a maximum at a certain mass density. The CA-IPA samples have a very narrow micropore distribution at about 0.5 nm. The mesopore distribution of the CA-IPA is widened and the average pore size increases as the mass density of the sample decreases. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 91: 3060–3067, 2004

The strong acid/weak base amphoteric ion exchange fibers with different ratios of acidic and basic groups and different grafting percentages were prepared by grafting styrene and 4-vinylpyridine onto polypropylene fiber and then sulfonating with chlorosulphonic acid, under various reaction conditions, such as the feed ratio of styrene and 4-vinylpyridine, monomers concentration, sulfonation temperature, and sulfonation time, swelling time, etc. The produced strong acidic and basic groups are the sulfonic group and the pyridyl group, respectively. Only one sul- fonic group is induced into an aromatic ring in most of PP-g-St-4VP and it is located in the para-position of styrene. The contents of the strong-acid group and the weak-base group of the PP-g-SO3H-Py fibers produced in this work are in the range of 1.98 to 4.22 and 2.33 to 4.24 mmol/g, respec- tively. The strong acid/weak based amphoteric fibers ob- tained possess good static adsorption property for basic and acidic amino acids, and they also have a good dynamic adsorption and elution property for amino acids like related strong acid ion exchange fibers. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 418 - 425, 2004

By solid-state 13C- and 31P-NMR, XPS, and FTIR, the chemical structure of activated carbon fiber–P (ACF-P) and its reaction with phosphoric acid were studied. Even when activated at low temperatures, these fibers developed a graphitelike carbon structure with a certain amount of phenol groups as well as acetal (or methylenedioxy) carbon. As expected, the oxygen-containing groups were greatly reduced at high activation temperatures. Different from the ACF-W, metaphosphoric acid (or polyphosphates) and a small amount of phosphorus exist on ACF-P. The original ACF-P activated at low temperature contained a lot of phosphoric acid, so it had to be washed with water to expose the large surface area. The washing process can be omitted for ACF-P activated at high temperature because most phosphorus compounds in fiber have volatilized. The ACF-P activated at lower temperature possessed a large amount of oxygen-containing surface groups and had enhanced adsorption ability for polar adsorbates. The remaining of metaphosphoric acid enhanced the adsorption of silver ion. The experimental results showed that the peaks of 31P-NMR, P2p-XPS, and FTIR at 1620 cm−1 shifted with the increase of activated temperature. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 87: 2253–2261, 2003

The dynamic adsorption behaviors of benzene vapor on phosphoric acid-activated carbon fiber (ACF-P) were investigated by gas chromatography. The experimental results showed that ACF-P that was activated at >350°C, like steam-activated carbon fiber (ACF-W), has good dynamic adsorption properties for benzene vapor. However, the saturation adsorption capacities of ACF-P and ACF-W are different. The dynamic adsorption conditions apparently do not affect the effluent concentration before the breakthrough point, but do change the operation loading and usage efficiency. The adsorbed ACF-P can be regenerated, and good dynamic adsorbability can be recovered by heating treatment. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 1841–1847, 2002

A facile method is developed to synthesize silicone-toughened unsaturated polyester (SUP-M) by monomer copolymerization of anhydrides and diols with hydroxyl-terminated silicone. The structures and molecular weights of the SUP-M resins were characterized by Fourier transform infrared spectroscopy and gel permeation chromatography, respectively. The gelation time and mechanical properties, including impact strength, flexural strength, and tensile strength, were investigated. The fracture behaviors were studied by scanning electron microscopy, and their glass-transition temperature and storage modulus were measured by dynamic mechanical analysis. The experimental results showed that the impact strength of SUP-M can be obviously improved through copolymerization with a small amount of silicone without decreasing its mechanical properties. The impact strength, flexural strength, and tensile strength of SUP-M-0.5 are as high as 12.5 KJ m−2, 131 MPa, and 59 MPa, which are increased by 76.1%, 21.2%, and 6.7%, respectively, compared with those of unsaturated polyester. Impacts on SUP-M with low silicone content produce a large number of evenly and regularly distributed continuous narrow crack bands combined with many evenly distributed branching crazes, which are of great benefit in absorbing a large amount of impact energy. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 135, 45562.