The potential application of biodegradable and biocompatible polymeric micelles formed by Pluronic F127 P104 as nanocarriers the antineoplastic drugs docetaxel (DOCE) doxorubicin (DOXO) is presented in this work. release profile was carried out under sink conditions at 37 °C analyzed using Higuchi, Korsmeyer–Peppas, Peppas–Sahlin diffusion models. cell viability HeLa cells evaluated proliferation counting kit CCK-8 assay. solubilized significant amounts DOCE DOXO, released them a sustained...

Water absorption and thermomechanical behavior of composites based on thermoplastic starch (TPS) are presented in this work, wherein the concentration agave bagasse fibers (ABF, 0–15 wt%) poly(lactic acid) (PLA, 0–30 is varied. Glycerol (G) used as (S) plasticizer to form TPS. Starch stands polymer matrix (70/30 wt/wt, S/G). The results show that TPS hygroscopicity decreases PLA fiber content increase. Storage, stress-strain, flexural moduli increase with and/or (ABF) while impact resistance...

Fixed-bed columns packed with chitosan-magnetite (ChM) hydrogel and chitosan (Ch) were used for the removal of arsenate ions from aqueous solutions at a pH 7.0. The effect flow rate (13, 20, 25 mL/h), height (13 33 cm), initial concentration (2, 5 10 mg/L) on column's efficiency As(V) is reported. maximum adsorption capacity (qb), obtained before allowed contaminant exceeded, (qe) when column exhausted, mass transfer zone determined. With this information, was calculated, which given by...

Foamed linear medium density polyethylene parts were prepared by rotational molding in biaxial mode, using different amounts of chemical-blowing agent (azodicarbonamide). Morphological and mechanical properties are presented discussed terms foam density, cell average diameter, open content. Internal air temperature the mold was measured as a function time. Significant differences observed between unfoamed foamed parts. The use an exothermic increased peak internal part cooling slower due to...

The removal of Cu(II) ions from aqueous solutions at a pH 5.0 was carried out using fixed-bed columns packed with alginate-chitosan (Alg-Ch) or sulfate (Alg-ChS) hydrogel beads. effect the initial concentration, flow rate, pH, and height column on amount Cu removed by breakpoint exhaustion point is reported. solution column's exit initially higher than that entrance, then decreased slowly. This increase attributed to proton transfer amino COO- groups hydrogel. operating conditions mass zone...

To promote osteointegration, bioactive cuttlebone particles containing collagen were used to fill an acrylic cement, varying filler concentration (0-50 wt%). Cuttlebone was characterized by X-ray diffraction, plasma atomic emission and FT-IR. Mechanical properties of the filled cement determined following ASTM procedures, included stress-strain, compression, bending, fracture toughness tests. For in vivo tests, three groups seven adult healthy rabbits prepared make implant parietal bone each...

This study evaluates the effect of agave fiber and nanoclay reinforcers over poly(lactic acid) (PLA) properties. Also, a compatibilizer based on glycidyl methacrylate PLA was used to enhance fiber-PLA interaction. The results showed that crystallinity increased with addition while inclusion decreased it. Tensile flexural moduli were by both reinforcements. fibers affect negatively tensile strengths, but they importantly recovered compatibilizer. Even though did not modify impact strength, it...

Abstract Bioactive cuttlebone Sepia officinalis particles that contain collagen were used to fill poly (methyl methacrylate‐ co ‐styrene) bone cements, varying size and concentration of filler particles. Cuttlebone was characterized by X‐ray diffraction plasma atomic emission spectrophotometer. Maximum reaction temperature cement setting time determined for composites reference (copolymer without filler), along with NMR determination residual monomer concentration. Mechanical properties...

Using a semicontinuous seeded emulsion polymerization process with gradual variation in feed composition, butyl acrylate (BA)/styrene copolymers were obtained (variable composition copolymers, VCCs). BA seed particles of two different diameters used to prepare copolymer materials 50–85 wt.% styrene. In each reaction, cumulative was followed by 1H-NMR; such data, histogram showing the relative content chains corresponding interval built. The VCCs presented higher moduli and ultimate...

Abstract A semicontinuous emulsion process varying comonomer feed composition in the course of reaction is used here to produce copolymer chains different as conversion proceeds. Polymeric material global and evidence branching are determined by 1H-NMR. The GPC beyond range where mechanical properties depend on molecular weight. Static dynamic variable copolymers exhibit highly improved type behavior for all tested compositions (styrene content between 30 85 wt%), showing high superiority...

Abstract Semicontinuous seeded emulsion copolymerizations, using 5 different types of feeding profiles comonomers (styrene/butyl acrylate, S/BA) were carried out, to vary in a gradual manner the composition copolymer chains formed throughout reactions (gradient copolymer, GCC). For comparison, equivalent core-shell type polymeric materials synthesized two stages (TS). In all reactions, S/BA global mass ratio was: 70/30. To estimate weight distribution (WCD) chains, cumulative styrene content...

Modified Chitosan was used for the removal of red dye 40 from aqueous solutions at a pH 5.0. The adsorption carried out making use fixed-bed columns packed with beads Alginate-Chitosan Sulfate (Alg-ChS) hydrogels. Two heights 13 and 33 cm, two feed rates (20 mL/h) were used. exit much higher than that entrance which can be explained by protons transfer solution to amino hydroxyl groups Alg-ChS carboxilate alginate. increase in favorable dye. breakthrough time amount removed decreased when...

In this work, the capability to use pine rosin as a biodegradable coupling agent/compatibilizer is studied.To formulate composites, post-consumer polypropylene and discarded agave fibers (as reinforcing agent) are coupled with (in pure or maleated form).Besides, poly(lactic acid) (PLA) poly(butylene adipate-co-terephthalate) (PBAT) compatibilized rosins prepare blends.For agent role, (Amberyl M-15A) compared commercial polyolefin (Epolene E-43), while for blends, two (Amberyls M-15A MP-30)...

To design the properties of a copolymer using free radical polymerization, semicontinuous process can be applied to vary instantaneous composition along conversion searching for specific spectrum chains, which termed as weight distribution (WCD) chains. Here, styrene-n-butyl acrylate (S/BA) system was polymerized by means emulsion process, varying comonomer feed obtain forced copolymers (FCCs). Five different feeding profiles were used, scheme chains rich in S (looking considerable modulus),...

Several methods to measure surface tension involve some inconveniences when applied moderate or highly viscous polymer solutions. Therefore, an improved version of the weight drop method (WDM) is proposed here. In addition, a comparative analysis carried out, including profile (DPM), selected planes (SPM), WDM and one here (WDSM), finding that WDSM as easy apply SPM WDM, although in practical conditions it much more accurate than either them. Moreover, allows reproduce results can be...

Abstract The usefulness of waste (mainly cellulosic) materials as a reinforcement for acrylonitrile‐butadiene rubber (NBR) compounds is shown in this work. tested are: henequen, pine, coconut, sugarcane husks, lignin, and wood sawdust. Their performance compared with that commercial (santocel solka), using the same copolymer composition without reference compound. Uniform particle size achieved by milling screening. For some materials, 6 mm fibers polymerfiber coupling agent are also tested....

Abstract In this work four different curing modes were used to crosslink a general‐purpose unsaturated polyester resin. Styrene was as monomer and glass fiber mat reinforcement. The included traditional convection oven, long‐wavelength infrared (IR) radiation medium‐wavelength IR or room temperature for an open‐curing condition without oven heating. Some samples cured using initiator only, others combining promoter. For curing, chamber 85°C. the samples, final conversion (using Fourier...