Marcin Masłowski

The use of rye, oat and triticale straw as fillers of natural rubber composites

Up to date, there are no evident research works carried out to improve and verify the physical, mechanical, barrier and damping properties of bioelastomer composites with addition of straw. Moreover, the problem of improving the reuse of straw is now demanding attention in the major cereal-growing areas of the world. The aim of this study was to receive knowledge of characteristic and producing multifunctional elastomer biocomposite filled with straw. Rye, oat and triticale were found to be active fillers improving wide range of rubber composites functional properties like: static mechanical, damping, barrier properties and hardness. The use of straw as a filler also increased cross-linking density. Dynamic-mechanical analysis indicates the presence of strongly developed secondary structure of examined fillers in vulcanizates. Moreover, all of the vulcanizates proved to be resistant to thermo-oxidative degradation. The application of straw as a filler allowed obtaining composites with lower value of oxygen index, that reflecting higher tendency of smoke generation. Introducing the straw into polymer matrix reduced the manufacturing costs of composites through the use of a significant amount of inexpensive and renewable filler. Furthermore straw fillers modify natural rubber, obtaining high-performance materials with meaningly enhanced applications.

Influence of lignocellulose fillers on properties natural rubber composites

The present article presents unreported yet in the subject literature examinations of the effect of a lignocellulose filler obtained from an alkalized wheat straw treated with di-potassium phosphate on the properties of natural rubber composites. The thermal and mechanical properties as well as the fire hazard of the composites obtained were tested also in the presence of an additive flame-retardant compound (poly(ammonium phosphate)), exploiting the synergism of its action with pentaerythritol, antimony trioxide, aluminum hydroxide and zinc borate. Based on the results obtained by the methods of thermal and mechanical analyses, micro-calorimetry and cone calorimetry, it has been found that the bio-filler increases, especially in the presence of additive flame-retardant, the resistance of the bio-composites tested to the action of fire, without a significant deterioration in their mechanical properties.

Magnetorheological Elastomers Containing Ionic Liquids

The term ionic liquid (IL) refers to a class of liquids that are composed solely of ions1. It is a synonym for molten salt. IL in a narrow sense often indicates room-temperature ionic liquid (RIL) that exists as a liquid at room temperature. Ionic liquids (ILs), which have been widely promoted as “green solvents”, are attracting much attention for applications in many fields of chemistry and industry due to their chemical stability, thermal stability, low vapour pressure and high ionic conductivity properties2. In recent years, ILs have been used in polymer science, mainly as polymerisation media in several types of polymerisation processes, including conventional free radical polymerisation3, living/controlling radical polymerisations (such as atom transfer radical polymerisations (ATRP), reversible addition-fragmentation transfer (RAFT))4, and ionic and coordination polymerisations5. When radical polymerizations are conducted in an IL, a significant increase of the kp/kt ratio is normally observed compared radical polymerizations conducted in other polar/coordinating solvents. As solvents for ATRP and RAFT, ILs facilitate the separation of the polymer from residual catalyst and reduce the extent of side-reactions. Applications of ILs as solvents for polymerisation processes have been reviewed by Kubisa6 and Shen and Deng7. However, application of ILs in polymer science are not limited to traditional polymerisation media. ILs have also been investigated as components of polymeric matrixes (such as polymer gels), as templates for porous polymers and as novel electrolytes for electrochemical polymerisations. This review focuses on recent developments and applications of ILs in the preparation of functional polymers. There is much current interest in ionic liquids. The much lower melting points of ionic liquids compared to those of inorganic salts can be partially attributed to the bulky cationic groups, i.e., the low charge density and incompatibility of the Coulombic attraction forces with steric hindrance. Ionic liquids have very low vapour pressures, although it was recently shown that they are distillable8. Therefore, they do not produce hazardous vapors (in contrast to many conventional organic solvents). Most ionic liquids have high ignition points, and they do not generate explosive air-vapour mixtures. They can act as solvents for chemical reactions, including catalytic reactions9. As a result of their interesting physical-chemical features ionic liquids have been extensively evaluated as environmentally friendly or “green” alternatives10 to conventional organic solvents for a broad range of organic synthetic applications. In addition, ionic liquids have

POSS as promoters of self-healing process in silicone composites

AbstractThis article focuses on the methods used to create self-healing silicone composites. It has been shown how incorporation of polyhedral oligomeric silsesquioxanes (POSS) molecules with acid and basic groups into silicone rubber affects the barrier properties, mechanical properties in room temperature or the influences on relaxation rates of the methylvinylsilicone rubber vulcanizates. Moreover, the presence of silsesquioxanes, their content and the way of composites preparation affect the amount of ionic bonds, as indicated by measurements of equilibrium swelling in toluene. The self-healing effect of preparing samples is best visualized by SEM images of samples after destruction and conditioning. Composites presented in this work based on the methylvinylsilicone rubber with fumed silica as the fillers were manufactured and studied. To obtain self-healing effect, various silsesquioxanes were used, such as amic acid-isobutyl POSS (AAIb-POSS), aminopropylisobutyl-POSS (APIb-POSS) and aminoethylaminopropylisobutyl-POSS (AEAPIb-POSS). Every tested sample demonstrated the ability to the self-treatment. The most significant effect was observed for system containing amic acid-isobutyl POSS/aminopropylisobutyl-POSS.

Natural Rubber Composites Filled with Cereals Straw Modified with Acetic and Maleic Anhydride: Preparation and Properties

This research paper aims to provide an examinations on biocomposites based on natural rubber (NR), natural straw fibers as well as their production techniques and properties. After pre-alkalization of the fillers, two main modification methods were carried out, with the usage of acetic or maleic anhydride to improve the adhesion of the fibers to the elastomeric matrix. Firstly, physicochemical characterization of straw particles, both pure and modified, using scanning electron microscopy (SEM), thermogravimetric analysis (TGA) and Fourier transmission infrared spectroscopy (FTIR) was performed. Moreover full characterization of the produced composites was also executed, which included: rheogical properties, static and dynamic mechanical properties, crosslinking density, damping properties, tear strength and resistance to simulated aging processes. Increased adhesion between modified straw fibers and the elastomeric matrix was observed for 10 phr filled composites, which was confirmed by dynamic mechanical thermal analysis (DMTA). In addition, the impact of the applied modifications was confirmed by higher values of the Payne effect, which resulted from the presence of developed secondary structure of the filler in vulcanizates. Furthermore, the crosslinking density of composites increased, which was reflected in the improvement of tensile properties, determined by tensile and tear strength and relative damping.

Evaluation of the Elastomeric Composite Self-repair Process for the Construction of Protective Gloves

Preliminary results of the implementation of self-healing polymers in all-rubber protective gloves are presented. The aim of the study was to evaluate the self-healing process of the elastomeric composite in PPE (personal protective equipment). Tests were performed for two types of materials based on methyl vinyl silicone rubber with and without a textile carrier. Assessment of the surface morphology of the materials was performed before and after the self-healing process. The protective properties, including tear, deformation and chemical permeation resistance were determined. Surface damage was simulated to reflect real changes that might occur during work. The materials were damaged by simulated puncture, cutting and abrasion. All tests were performed for samples without damage, with micro damage as well as after self-repair. The results obtained confirm the possibility of using the elastomeric composite tested in the construction of protective gloves and showed the effectiveness of the self-healing process.

Silanized cereal straw as a novel, functional filler of natural rubber biocomposites

The aim of the presented research paper was to modify the biofiller in the form of milled cereal straw with 3-aminopropyl(diethoxy)methyl silane, and apply it to the natural rubber. To determine the material properties, an in-depth characterization of both the treated lignocellulosic material and the composites was studied. On the basis of thermogravimetric analysis, scanning electron microscopy, infrared spectroscopy and analysis of contact angle measurements, it was found that the silanization process significantly influenced thermal stability and hygroscopicity of the straw, its hydrophobicity as well as dispersion in polymeric matrix. Analyses of the new composites included static and dynamic mechanical properties, hardness, and barrier and damping properties, all of which showed improvement. This was because of improved interactions at the filler–elastomer, which resulted from better adhesion of the treated bio-additive to natural rubber. Biocomposites have also demonstrated greater resistance to flammability as well as thermo-oxidative aging processes. The research clearly indicates the application potential of these new multifunctional and biocompatible materials.Graphical abstract