Fine Rubber Research Articles

Evaluation of the Applicability of Waste Rubber in Insulation Panels with Regard to Its Grain Size and Panel Thickness

This paper explores the effect of waste rubber grain size on the porosity, modulus of elasticity, thermal properties, and soundproofing performance of polymer composites with different thicknesses (10, 15, and 20 mm). All properties were tested in accordance with European standards, with the exception of porosity, which was measured using Archimedes’ principle. The findings indicate that with a consistent amount of polyurethane glue, finer rubber grains result in composites with higher porosity, leading to a lower modulus of elasticity but enhanced thermal and sound insulation. In contrast, coarser rubber grains produced composites with lower porosity and a higher modulus of elasticity, though with slightly reduced thermal insulation and significantly worse soundproofing. A combination of fine and coarse rubber grains provided a balanced performance, offering both good thermal and sound insulation while maintaining a high modulus of elasticity. Among the thicknesses tested, 15 mm was identified as optimal, combining a relatively high modulus of elasticity, low thermal conductivity, and better airborne sound insulation index. Future research will focus on applying this composite in concrete building products that meet noise protection and energy efficiency standards.

Experimental Investigation and Machine Learning Prediction of Mechanical Properties of Rubberized Concrete for Sustainable Construction

Concrete is widely used in civil engineering applications and the natural aggregates which used in concrete are scarce, but its demand is increasing. The disposal of rubber tyres poses a significant environmental challenge, as their decomposition releases harmful chemicals into the soil and water bodies over many years. Decomposition of tyres should be done in a smart way and hence came the emergence of mixing recycled rubber crumbs into concrete as Rubberised Concrete (RC). This paper provides an in-depth analysis of the mechanical properties of concrete such as Compressive Strength (fck), Tensile Strength (ft), Flexural Strength (fcr) of 7, 14, 28 days in replacement of fine aggregate with fine rubber (FR), and Coarse Aggregate with Coarse Rubber (CR). The results indicate that RC is more suitable for structural applications, including Reinforced Concrete columns, beams, slabs, than conventional concrete. The primary objective of the article is to explore the potential use of recycled rubber crumbs in concrete, referred to as Rubberised Concrete (RC), and to analyze its mechanical properties such as compressive strength, tensile strength, and flexural strength over different curing periods. Additionally, machine learning (ML) based prediction model has been developed for various strength characteristics of concrete mixtures at 28 days. The hyperparameter optimization using Grid Search CV with fivefold cross-validation have been performed to obtain the best hyperparameters. The model’s performance is evaluated using metrics like MAE, MSE, RMSE, and R-squared values. Results reveal varying performances among different ML algorithms for predicting flexural, tensile, and compressive strengths.

Production of rubberized concrete utilizing reclaimed asphalt pavement aggregates and recycled tire steel fibers

The integration of waste tire elements into concrete, specifically granular rubber and discrete steel fibers, signifies a substantial advance in the pursuit of sustainable alternatives for rigid concrete pavements. This incorporation not only improves the ductility of rigid concrete pavements, but also augments their energy absorption capabilities. Similarly, replacing natural aggregates in concrete with reclaimed asphalt pavement (RAP) aggregates makes a large contribution to the reduction of negative environmental impacts, while conserving natural resources from depletion. This investigation explores the potential application of recycled rubber particles from waste tires (WTRR) and RAP aggregates as partial substitutes for natural fine aggregates, and evaluates their impact on the performance of rigid concrete pavements. Eight mixes were cast, each with two variables: (i) fine aggregate type (fine rubber (FRu) aggregates, fine asphalt (FAs) aggregates, and combinations of both types of aggregate) replacing 50 % of the natural fine aggregate; and (ii) waste tire recycled steel fibers (WTRSF) content (0 and 40 kg/m3). The axial compressive stress–strain, flexural load–deflection, and direct shear strength behaviors, together with the dry unit weight and volume of permeable voids for all concrete mixes were investigated and compared. The results show that, although the flexural and shear strengths decrease with the inclusion of FRu and/or FAs, the use of WTRSF noticeably mitigates the losses in strength that arise from the use of WTRR and/or RAP aggregates alone. The inclusion of WTRSF enhances the strain capacity of the concrete and allows the development of adequate post-peak energy absorption capacity in flexural and shear loading. Additionally, the dry unit weight of the proposed composites decreased by as much as 8 %, and their volume of permeable voids lies within the limits of high-durability concrete mixes (9–12 %). Hence, the proposed sustainable concrete composites are promising composites for rigid concrete pavement construction.

Investigation of modification of petroleum bitumen with fine rubber crumb

Currently, in the world, due to the constant desire for recycling, many countries are considering the possibility of using rubber waste on roads. Bitumen modification for roads in Kazakhstan is considered one of the most suitable and popular approaches. This article presents the results of research on the modification of bitumen with rubber chips obtained from rubber waste. The document describes in detail the details of using rubber chips as bitumen modifiers, with particular emphasis on how they can potentially be used to improve bitumen performance and road durability. A wet process is used to produce rubber-bitumen binders. The wet process modifies the asphalt binder directly by pre-mixing with rubber crumbs at elevated temperatures, it leads to the fact that the material turns out to be the most stable, with increased elasticity and viscosity at high temperatures. The main physical and mechanical characteristics of the modified bitumen were determined after standard tests: penetration and plasticity, softening temperatures. The morphology of the modified bitumen was studied using scanning electron microscopy. The results confirm that bitumen modified with a rubber crumb with the addition of SBS meets the requirements for a polymer-bitumen binder of Kazakhstani standards and, according to its physico-chemical characteristics, is suitable for the production of modified bitumen.

Ground Tire Rubber as a Sustainable Additive: Transforming Desert Sand Behavior

Managing waste tires presents a significant challenge globally, particularly in regions experiencing high temperatures and shortage of landfill sites. This issue is affecting countries like Kuwait, where the abundance of waste tires is a major source of environmental and safety risks, particularly during the intensely hot summer months. This extreme heat has sparked numerous fires, leading to substantial air pollution due to thick black smoke. Given the limited disposal options, recycling waste tires and finding practical applications for ground tire rubber (GTR) is essential. To address the challenge, a comprehensive laboratory testing program was conducted, using locally produced rubber aggregates as an additive to Kuwait's local surface sands. Two new variables were examined namely the size and gradation of the GTR, and the density of the compacted mixes. For this purpose, two different sizes of rubber aggregates, fine and coarse produced locally, were utilized, and the impact of relative compaction on the strength and compressibility of the mixtures was investigated by testing samples compacted to the maximum density and to 95% of the maximum density. The results suggest that combining local surface sands with rubber tire additives results in a lighter, more permeable, and compressible material, contributing significantly to sustainable waste management. With 20% rubber additive the maximum dry density decreased by nearly 20%, and the permeability increased by 1.74–3.11 times and the compression index increased by 6.15 and 3.8 times with fine and coarse rubber respectively. The angle of friction remained unchanged at 36° with the addition of coarse rubber and decreased by 3°–4° with fine rubber. The change in behavior although not an increase in the strength and stiffness, offers a range of suitable practical applications in civil engineering and environmental management, including use as a drainage layer, embankment construction on soft ground, earth fill around retaining walls, an additive in asphalt mixes, and in manufacturing compressible tiles for sports facilities.

Recycling of landfill waste tyre in construction materials: Durability of concrete made with chipped rubber

The goal of current research is to study the effect of waste tyre as a replacement for coarse aggregate at high levels in concrete for non-structural applications to address one of the serious environmental concerns. To reach this aim, waste rubber in a size range of 10–15 mm which needs less energy and cost for grinding compared to fine rubber was used. The total volume of coarse aggregate was substituted by rubber at the rates of 25%, 50%, 60%, 70% and 80%. Mechanical properties were studied through compressive and flexural strength and hardened density tests. Moreover, durability was comprehensively investigated via water absorption, drying shrinkage, electrical resistivity, chloride migration, carbonation resistance and resistance against acid attack tests. Sound absorption performance of different mixes at low and high frequencies were also compared to monitor the impact of rubber content. The results indicated that by the addition of rubber mechanical properties reduced, nevertheless, durability improved. Using rubber enhances the concrete ductility and reduces the density making it appropriate for lightweight concrete. The chloride migration coefficient was reduced up to 80% and electrical resistivity increased up to 87%, by using 80% rubber. Besides, rubberised concrete developed in this research demonstrated superior functional advantages over plain concrete in terms of acoustic performance and sustainability. Despite having lower strength by using rubber in concrete, rubberised concrete made with high content of cost-effective coarse rubber particle is appropriate for non-structural usages particularly in regions where either possibility of aggressive environment is a concern or noise attenuation is critical.

Mapping of Rubber Forest Growth Models Based on Point Cloud Data

The point cloud-based 3D model of forest helps to understand the growth and distribution pattern of trees, to improve the fine management of forestry resources. This paper describes the process of constructing a fine rubber forest growth model map based on 3D point clouds. Firstly, a multi-scale feature extraction module within the point cloud column is used to enhance the PointPillars learning capability. The Swin Transformer module is employed in the backbone to enrich the contextual semantics and acquire global features with the self-attention mechanism. All of the rubber trees are accurately identified and segmented to facilitate single-trunk localisation and feature extraction. Then, the structural parameters of the trunks calculated by RANSAC and IRTLS cylindrical fitting methods are compared separately. A growth model map of rubber trees is constructed. The experimental results show that the precision and recall of the target detection reach 0.9613 and 0.8754, respectively, better than the original network. The constructed rubber forest information map contains detailed and accurate trunk locations and key structural parameters, which are useful to optimise forestry resource management and guide the enhancement of mechanisation of rubber tapping.

Flexural behavior of steel fiber reinforced concrete beams comprising coarse and fine rubber and strengthened by CFRP sheets

Despite having many advantages, using rubber to produce reinforced concrete members like beams is still restricted. When there is more waste tire rubber in concrete structures, rubber concrete's flexural and compressive strengths gradually decrease. However, this study used steel fibers to improve compressive strength and externally bonded carbon fiber-reinforced polymer (CFRP) sheets to increase flexural strength. Four groups of three reinforced concrete beams each were established for the study's use. The first and third groups of concrete beams used a volumetric replacement of fine and coarse aggregates with 5% and 10% waste tire rubber. However, steel fibers were added to the second and third groups at a rate of 1.25% of the concrete volume. Waste tire rubber and steel fibers were not replaced or added to the fourth group, the main reference group. The dimensions of each beam were 2.1×0.2×0.3 m. A concrete beam's first member is always free of external reinforcement, followed by its second member, which has one layer, and its third member, which has two layers of CFRP sheet. ABAQUS, a finite element analysis program, was used numerically to represent the third strengthening layer. The results showed that strengthening the reinforced rubberized concrete beams with a single layer of CFRP sheets increased the load at first crack and failure by 8.57% and 17.64%, respectively, compared to the unreinforced reference beam, compensating for the loss caused by the production of rubberized concrete and adding additional flexural strength. These loads increased by 31.43% and 26.45%, respectively, due to the steel fibers added to the beams containing these waste tire rubber. Strengthening with two layers of CFRP sheets increased the load at first crack and failure by 17.14 and 34.27, respectively. The steel fibers added to the beams that contained these amounts of waste tire rubber, on the other hand, caused these loads to increase by 42.86 and 49.23%, respectively. Strengthening with three layers numerically results in an exponential increase in load at the first crack and the failure by 8.03 and 52.88%, respectively. On the other hand, the loads on the beams that contained these quantities of waste tire rubber increased by 50.49% and 104.47%, respectively, when steel fibers were added to them.

Flexural Behavior of Reinforced Rubberized Reactive Powder Concrete Beams under Repeated Loads

Non-biodegradability of rubber tires contributes to pollution and fire hazards in the natural environment. In this study, the flexural behavior of the Rubberized Reactive Powder Concrete (RRPC) beams that contained various proportions and sizes of scrap tire rubber was investigated and compared to the flexural behavior of the regular RPC. Fresh properties, hardened properties, load-deflection relation, first crack load, ultimate load, and crack width are studied and analyzed. Mixes were made using micro steel fiber of the straight type, and they had an aspect ratio of 65. Thirteen beams were tested under two loading points (Repeated loading) with small-scale beams (1100 mm, 150 mm, 100 mm) size. The fine aggregate is replaced by 5, 10, and 15%, respectively, with crumb rubber. While replacement of silica fume was 10, 20, 30, and 50%, respectively, with very fine rubber. Also, chip rubber was added to the mixture as coarse aggregate with 5, 10, and 15%. Five tested beams were chosen as case studies to analyze and compare the results of the ABAQUS software with the experimental results. The results showed that the flexural behavior of RRPC beams that contains rubber was acceptable when compared with the flexural behavior of the RPC beam (depending on load-carrying capacity). The crack width was decreased by including waste rubber and steel fibers. There is a satisfactory agreement between the results of the numerical analysis and the results of the experimental testing. Slight ultimate load differences are targeted between the effects of the monotonic loading and the repeated loading.

Preparation of terminal blend/ grafting activated crumb rubber composite modified asphalt based on response surface methodology

Recycling waste tires, crushing them into crumb rubber (CR) and adding them to asphalt can effectively improve the performance and prolong the service life of asphalt pavement. However, the crumb rubber modified asphalt (CRMA) prepared by aforementioned process is prone to segregation during storage and transportation. The terminal blend rubber asphalt (TB) prepared with fine rubber powder by high-speed shearing at high temperature for long time, which effectively improves the storage stability and working performance of crumb rubber modified asphalt, but reduces the high-temperature performance. In this study, grafting activated crumb rubber (GACR) was incorporated into TB to improve its high temperature performance without impairing storage stability. Using shearing temperature, shearing time and grafting activated crumb rubber content as influencing factors, the response surface method (RSM) was carried out to optimize the preparation process. The results indicated that 180°C was a critical temperature, and the swelling of crumb rubber dominated with the temperature below it, but the desulfurization prevailed with the temperature above it. The extension of time favored the swelling of crumb rubber at low temperature but promoted desulfurization at high temperature. With the increase of crumb rubber content, the high temperature performance of modified asphalt improved whereas the storage stability deteriorated. According to the determination of response values and the prediction of optimal values, the suitable preparation conditions and parameters were recommended as shearing temperature of 190°C, shearing time of 90 min, and GACR content of 15%. The composite modified asphalt prepared through the optimized process showed good high temperature stability and storage stability.

Reuse of waste rubber in pervious concrete: Experiment and DEM simulation

The reuse of waste rubber has a profound impact on environmental protection and resource recycling. To evaluate the feasibility of adding waste rubber into pervious concrete, the effects of rubber content and particle size on the mechanical properties of pervious concrete are investigated through experiments and discrete element method (DEM) simulation. The compressive failure mode of pervious concrete gradually transits from tensile failure to shear failure with the increase of rubber content, showing a decrease in compressive strength, and the larger the particle size is, the stronger the attenuation effect on the strength is. Rubber particles play a role in isolating coarse aggregates from the cement matrix and form a weak bond with the matrix, showing a weak bridging effect in stress transmission at the left and right ends of the crack, so that the splitting tensile strength of pervious concrete significantly decreases with the increase of rubber content, and the weakening effect of coarse rubber on the splitting tensile strength is stronger than that of fine rubber. Due to the low strength of rubber itself and weak bonding with cement matrix, pervious concrete with high rubber content breaks in advance at the bottom of the midspan, resulting in the decline of flexural capacity, and it decreases more obviously with the increase of rubber size. Although the direct tensile strength of pervious concrete gradually decreases with the increase of rubber content, the addition of rubber improves the plasticity of pervious concrete. Moreover, the plastic reinforcement effect of pervious concrete is the strongest when the rubber content reaches approximately 10%, and this toughening effect increases with the decrease of rubber size. On the basis of experimental research, a universal DEM model considering rubber content and particle size is established, which can well predict the mechanical performance of rubberized pervious concrete in terms of strength, failure mode, elastic modulus and ultimate strain.

Strength and cracking resistance of concrete containing different percentages and sizes of recycled tire rubber granules

In order to use recycled materials in the composition of greener and cleaner concrete products, it is vital to ensure that the produced concrete have the appropriate level of strength. This paper investigates the effect of gradation (size) and percentage of recycled rubber granules on the physical parameters (slump and density), strength parameters (tensile and compressive strength values), and in particular the crack initiation and propagation characteristics (under the opening, shearing, and tearing modes). The tensile strength, compressive strength, fracture toughness (KIc, KIIc, and KIIIc), and fracture energy values at the initial crack initiation and ultimate failure propagation stages were determined by testing specimens containing 0, 1, 2, 4, and 12% of fine and coarse recycled rubber granules. Rubber particles were graded in two distinct ways so that they could serve as both filler and granules. In contrast to fine rubber granules, the addition of coarse granules had a positive effect on mode-II and mode-III fracture toughness. But, the addition of fine and coarse rubber granules reduces mode I fracture toughness. The analysis of fracture values indicates that coarse rubber granules have a positive effect on the post-peak failure energy absorption (i.e., the crack propagation stage) of all fracture modes. However, this increase in fracture energy for the fine rubber combination was only observed for mode-II fracture stress. The fracture toughness and fracture energy values of the similar concrete were empirically determined based on their corresponding tensile strength. The link between fracture toughness and fracture energy values was also discovered. According to the experimental results, the concrete containing 4% coarse rubber granules provides good mechanical and cracking resistance properties.

Fabrication of Fine Rubber Valves using 3D Printed Resin Molds and Prototype Stabilizer for Off-Pump Coronary Artery Bypass Surgery

Fabrication of Fine Rubber Valves using 3D Printed Resin Molds and Prototype Stabilizer for Off-Pump Coronary Artery Bypass Surgery

Electrical Resistivity of Crumb Rubber Concrete (CRC) exposed to coastal zone- An Experimental Investigation

Electrical resistivity is a material property that can be used for analysis of concrete durability and also can be used to determine early age characteristic of fresh concrete. Electrical resistivity has developed as a new form of non-destructive testing technique. In this study, an experimental study is carried out to determine the electrical resistivity of crumb rubber concrete exposed to normal and coastal environment. Crumb rubber concrete (CRC) is a concrete in which sand is replaced with fine rubber crumb obtained by shredding of waste vehicle tires. In this study, sand was replaced up-to 15% in multiples of 2.5% and then a set of samples were kept for curing and exposure in normal environment and other set of samples were exposed to coastal environment along the coast of Visakhapatnam, Andhra Pradesh. The result obtained indicated that CRC samples showed lower electrical resistivity in the initial days and then resistivity increased at later stages. Chloride ingression test was also conducted on the samples which indicated that crumb rubber concrete showed better resistance to chloride ion penetration. Overall, the result analysis expressed that samples exposed to coastal zone showed lower resistivity, and CRC samples in case of both curing methods and exposure cases showed better resistivity to electrical conduction and chloride ingression than normal concrete samples. So as CRC shows better durability properties than normal concrete, it can be opted as a choice for concrete structures in coastal areas.

Mode I and mode II fracture toughness and fracture energy of cement concrete containing different percentages of coarse and fine recycled tire rubber granules

The effect of adding recycled tire rubber granules on pure mode I and II fracture behaviors of ordinary cement concrete is investigated using a testing specimen called the Edge Notch Disc Bend (ENDB). Several ENDB samples containing coarse and fine rubber granules with weight percentages of 0, 1, 2, 4, and 12% are tested to obtain the corresponding values of the fracture toughness and fracture energy besides the compressive strength measurement. The results showed the noticeable effects of both granule type (i.e., fine and coarse) and percentage of granules on the fracture characteristics of the tested cement concrete mixtures. The addition of up to 4% coarse grain granules can provide concrete mixtures with acceptable fracture characteristics. However, the greater percentage of rubber granules noticeably reduces the performance of concrete against cracking. The relationships between fracture characteristics (including modes I and II fracture toughnesses and fracture energy values at the onset of peak load and final failure stage) were explored in terms of the common compressive strength index of the tested concrete mixtures. In general, fairly linear correlations were obtained between the cracking resistance indexes and the compressive strength of the tested concrete materials.

ОБЕСПЕЧЕНИЕ ТЕХНОСФЕРНОЙ БЕЗОПАСНОСТИ ПРИ ПРОИЗВОДСТВЕ ЭМУЛЬСИОННЫХ КАУЧУКОВ

Synthetic polymer materials are in high demand due to their exceptional properties. Their main consumers are the tire and rubber industries. When producing synthetic rubbers, there is a loss of polymer in the form of fine crumb rubber, which is formed at the final stage of their production. Today, the removal of this crumb from the wastewater of latex rubber extraction plants is an urgent issue. The results of a study on the extraction of fine rubber crumbs are presented. The task is solved by using an apparatus for separating water phases in the technology, which allows more complete and rational use of expensive products of chemical and petrochemical production, increase productivity and environmental friendliness of production, which leads to an increase in technosphere safety in general. The optimal flow rates of aqueous phases passed through the spiral belt of the filter element, which is 15–25 m/s, have been determined. The separated water stream containing concentrated fine rubber crumb is returned to the styrene-butadiene latex coagulation stage. The purified water phase after the filter element is collected in a separate collector and used to prepare solutions of coagulating and acidifying agents. The additional introduction of finely dispersed rubber crumbs into the composition of the resulting coagulum do not lead to a deterioration in the basic physical and mechanical properties of the resulting rubbers and vulcanizates. The proposed method for industrial wastewater treatment improves safety in the technosphere.

Solvent-free electrospinning of liquid polybutadienes and their in-situ photocuring

A single-step approach to rapidly convert low molecular weight polybutadienes into fine rubber crosslinked fibers and nonwoven mats without using any heat or solvent was described. This environmentally friendly method consisted in the electrospinning at room temperature of liquid polybutadiene and polybutadiene-graft-maleic anhydride polymers without any solvent; the flying jet was irradiated to trigger the in-situ curing of the forming fibers at ambient conditions, obtaining a good control over the fibrous morphology and enhancing the performance of the membranes. The kinetics of the photo-crosslinking reaction was studied through FT-IR spectroscopy. Liquid polybutadiene-graft-maleic anhydride polymers demonstrated a faster rate of photocuring, compared to neat polybutadienes. In order to further speed up the reaction, a thiol-based crosslinker and a photoinitiator were introduced into the formulations. The photo-induced crosslinking was more efficient as different reactions concomitantly took place: besides the thiol-ene crosslinking involving the multifunctional thiol crosslinker, the oxidation of the polybutadiene chains and the esterification of the maleic anhydride moieties occurred. Moreover, a polar additive was used to control the electrospinning process by lowering the viscosity and increasing the electrical conductivity. The structural, thermal and surface properties of the fabricated polybutadiene-based electrospun membranes were assessed. The membranes exhibited an excellent morphology stability, high insolubility, good thermal properties and a pronounced hydrophobic character.

On the acoustical performance of eco-friendly cementitious composite with recycled fine rubber particles

Enhancing the sound absorption capacity of cement-matrix composites with fine particles of rubber tires is studied. Ordinary Portland Cement (OPC)/ waste rubber particles (WRP) were blended with the ratios of 100/0, 95/5, 85/15, and 75/25 wt%, respectively, then mixed with water. The sound absorption coefficient (SAC) and noise reduction coefficient (NRC) were assessed using the two microphones method. The specific sound transmission loss (SSTL) was calculated to show the correlation between the STL and the density of the prepared samples. The WRP dispersion in the matrix of the composite was analyzed using a digital microscope and ImageJ program to investigate the homogeneity of dispersion. The morphology and microstructure of the formed hydration products were examined by environmental scanning electron microscope (ESEM). The Physicomechanical properties: compressive strength, water absorption, apparent porosity, and bulk density of the hardened composites were measured after 28-days of hydration. The results showed that replacement of OPC with 5, 15, 25 wt% WRP led to an increased sound absorption compared to the control sample. Increasing the dose of the WRP caused the reduction of voids content in the hardened cement pastes. The NRC values were improved by 109, 27.3, and 63.6% than the control sample for 5, 15, and 25 wt% WRP, respectively.

ANALYSIS OF WATER PERFORMANCE OF COATING MORTARS INCORPORATED WITH TIRE RUBBER

This paper analyzed the behavior of mixed mortars incorporated with rubber from the tire retreading process, based on partial sand substitution. The content of rubber incorporation in the mortars was 5%, 10%, 15%, and 20% by volume. The different granulometries of rubber were denominated as thick (passed through a sieve # 1.19 mm) and fine (passed through a sieve # 0.60 mm). Tests were performed to evaluate water retention, capillary absorption, drying, immersion absorption, water vapor permeability, and permeability to water under pressure. The results showed that the fine rubber was distinguished by its higher retention of water at the contents of 15% and 20%, lower absorption via both capillary and immersion, higher drying capacity, higher permeability to water vapor, and lower permeability to water under pressure.

About the study of compounds incorporating rubber tires

In this paper we have studied some physical characteristics of gypsum composites incorporated with two different tire rubber granulometry. The experimental program was formed by the following tests: consistency (mini-slump), compressive strength and scanning electron microscopy (SEM). The rubber used in the composites came from the retreading of tires with 5 and 10% incorporation in relation to the plaster mass and the two different granulometry used were denominated thicknesses (# 0.6 mm) and thick (# 1.19 mm ). The results were compared with the control paste, in which there was no incorporation of rubber. The rubbers of different granulometry stood out in different points. The thin rubber presented a compressive strength close to the value observed in the control, with an addition of 5% by mass, which may be due to its adherence to gypsum paste, which occurred in a less porous manner and with a closer interface between the rubber particles and pulp, observed through the SEM. The thick rubber presented the best results in consistency, contributing to the workability of the pulp, which was also observed in SEM, where the thick rubber presents less adherence to the gypsum plaster, compared to the composite with incorporation of fine rubber. It was possible to affirm, then, that rubber as residual material presented interesting characteristics in applications in plaster composites.