Alternative Filler Research Articles

Enhancing the Performance of Layered Wood Composites Through the Non-Food Application of Dietary Fiber in Their Bonding Matrix

Rye flour is a commonly used filler in plywood production, made from finely ground rye grains. It enhances glue viscosity, ensuring even distribution and better adhesion, which improves the plywood’s mechanical properties, dimensional stability, and resistance to warping. Additionally, rye flour increases the plywood’s strength and durability, making it more resistant to mechanical damage and external factors. Its affordability and availability further support its widespread use in plywood production. However, the growing availability of new raw materials has sparked interest in alternative fillers, especially considering food waste challenges caused by low demand or poor household management. This study explores the potential of spirulina, bamboo flour, lupine flour, and coconut flour as alternative fillers to rye flour, being part of the food chain, in three-layer plywood production. Plywood panels were manufactured using birch and pine veneers, urea-formaldehyde resin, and varying filler contents (10, 15, and 20 parts by weight/pbw). Key mechanical properties were evaluated, including modulus of elasticity (MOE), modulus of rupture (MOR), shear strength, density profile, and filler water absorption. The highest MOE for hardwood plywood was observed with coconut flour (20 pbw, 17,228 N mm−2). Conversely, the lowest MOE values were recorded for coniferous plywood with spirulina (8440 N mm−2). For MOR, the best performance in softwood was achieved using lupine flour (10 pbw, 113 N mm−2), while coconut flour yielded the highest MOR in hardwood plywood (20 pbw, 177 N mm−2). Spirulina exhibited the lowest MOR (72 N mm−2, 15 pbw). Shear strength peaked with lupine and coconut flour. The filler composition determines adhesive properties and bond performance through water absorption, structural interactions, and filler content optimization. These findings emphasize the potential for fine-tuning alternative fillers to achieve desired mechanical performance, ensuring sustainable and efficient plywood production. These also demonstrate the potential of certain alternative fillers, particularly coconut and lupine flours, excluded from the food value chain, in improving specific properties of plywood.

OPTIMAL PROPERTIES OF SURFACE MODIFIED CELLULOSE AS FILLER IN POLYMER COMPOSITES

The research and development of new materials that are not only functional, but also ecologically acceptable, is a key aspect in many branches of industry. Such materials include elastomeric composites reinforced with alternative fillers such as cellulose. Cellulose is a renewable and biodegradable alternative to traditional fillers used in elastomeric composites. The main disadvantage of this biopolymer is its poor compatibility with the hydrophobic matrix and low mechanical strength. The free hydroxyl groups on the cellulose surface allow for a wide range of surface modifications. In this work, we focused on the chemical modification of cellulose using two different silanes due to their ability to react with the free hydroxyl groups on the surface of cellulose. This work deals with the characterisation of thermal stability of surface modified cellulose used as filler in polymer composites. Cellulose modified in this way was used in the amount of 45 phr as a filler in the preparation of elastomeric composites with natural rubber (NR) matrix. The NR composite filled with surface modified cellulose was characterized by TG/DSC, IR spectroscopy, XRD and scanning electron microscopy.

The Influence of Various Modifications of Hazelnut Shell Flour as Potential Filler in Plywood Technology.

This study investigates the potential of utilizing hazelnut shells (HS) as an innovative filler in three-layer plywood technology, addressing the growing need for sustainable, high-performance materials. Traditional plywood production relies on adhesives enhanced with various fillers to improve physical, mechanical, and operational characteristics. This research explores using native, chemically modified, and activated carbon derived from hazelnut shells as fillers in urea-formaldehyde (UF) resin. The produced plywood's mechanical properties, water absorption, and formaldehyde emissions were thoroughly analyzed. Key findings demonstrate that incorporating 10 part by weight (pbw) native hazelnut shell flour significantly enhances the modulus of rupture (MOR) to 138.6 N mm-2 and modulus of elasticity (MOE) to 13,311 N mm-2. Chemically modified hazelnut shell flour achieves optimal results at 5 pbw, while activated carbon from hazelnut shells, even at 1 pbw, markedly improves bonding strength (2.79 N mm-2 referred to 0.81 N mm-2 for reference sample without filler added). Notably, activated carbon effectively reduces formaldehyde emissions (2.72 mg 100 g-1 oven dry panel referred to 3.32 mg 100 g-1 oven dry panel for reference samples with 10 pbw filler) and improves water resistance, indicating better further dimensional stability and lower environmental impact. The study also shows that excessive filler content negatively affects strength parameters, confirming the importance of optimizing filler concentration. These results highlight the potential of hazelnut shells as an eco-friendly alternative filler in plywood production, contributing to waste valorization and environmental sustainability. This study supports the practical application of hazelnut shell fillers, promoting a circular economy and reducing reliance on traditional, less sustainable materials, thus providing a valuable solution for the wood composite industry.

Paving the Way for Sustainability: A Study on Porous Asphalt Mixtures Reinforced with LDPE Plastic Waste and Freshwater Mussel (Pilsbryoconcha Exilis) Shell Filler

This study aimed to explore the impact of different fillers, namely conventional (stone ash) and alternative (mussel shell powder), along with varying percentages of Low-Density Polyethylene (LDPE) additives, on the performance of porous asphalt mixtures. Asphalt mixtures' Marshall Stability and Flow were examined with LDPE percentages of 0%, 2%, 4%, and 6%. Results highlighted that the choice of filler and LDPE content significantly influences the mixture's stability and flow. A shift from 100% stone ash to 50% mussel shell powder resulted in a slight decrease in stability for 0% and 2% LDPE. In contrast, the stability was notably higher for 4% and 6% LDPE, including the alternative filler. Mixtures with 100% stone ash exhibited increased flow values with rising LDPE concentrations, while mixtures with 100% mussel shell powder showed an opposite trend. Furthermore, mixtures containing mussel powder generally had higher flow values than those with stone ash at similar LDPE percentages. The study underscores the intricate relationship between filler types and LDPE additives in influencing the properties of asphalt mixtures. These findings pave the way for the potential use of alternative fillers in asphalt mixtures, emphasizing the importance of understanding material interactions for optimal pavement design.

Evaluating thermal activated coal gangue as alternative filler in asphalt binder using rheological experiments and molecular dynamic simulation

Asphalt mastic, an important raw material in asphalt pavement, is a mixture of asphalt binder and mineral filler. This study utilized coal gangue (CG) as alternative of natural filler in asphalt mastic, which has benefits to recycling solid waste and saving non-renewable resource. In order to achieve performance improvement of CG asphalt mastic (CGAM), thermal activation approach was applied to treat CG particles from 450 ℃ to 900 ℃. Before and after treatment, the surface morphology, mineral components and size distribution were characterized via scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray fluorescence (XRF) and laser particle size analyzer. Meanwhile, the dynamic shear rheometer (DSR) and bending beam rheometer (BBR) experiments were conducted to compare the rheological responses of CGAM at high and low temperatures. Further, the interfacial behavior between asphalt binder and CG filler is simulated by molecular dynamic (MD) method, aiming to explore the interaction mechanism at atomistic scale. Results show that the activated CG possesses a smaller particle size and a rougher surface by comparison in virgin one (i.e., unactivated CG). And the calcination process results in the crystal phase transition of CG and the proportion increase of alkali minerals, contributing to the stronger interaction ability and higher adhesion energy with asphalt binder. Owing to the positive changes of CG during calcination process, the corresponding CGAM exhibits superior deformation resistance property under recycling loads at high temperature and flexural creep ability at low temperature, especially when the calcination temperature rises to 750 ℃.

Coffee grounds as sustainable filler for bio‐based rubber composites

AbstractUsing biological/renewable resources as filler or modifier in both thermoplastics and rubbers has been of a great interest in order to reduce negative effects of traditional petroleum/natural gas based fillers. In this study, the main goal was the use of spent (waste) coffee grounds as a natural alternative filler to carbon black in acrylonitrile butadiene rubber (NBR) based compounds. Carbon black (CB) was partially replaced with fresh as well as spent coffee grounds (SCG) in NBR compound formulation. Stabilization effect of fresh coffee grounds was also investigated. Cure characteristics, physico‐mechanical, thermal, morphological, and dielectric properties of the bio‐based composites were tested and compared with the control (reference) compounds. Processability has been affected positively in the case of using coffee grounds thanks to the presence of triacyl groups in coffee. Up to 20% higher elongation at break values were measured when coffee is partially replaced with CB. Abrasion loss and oil resistance could be retained for coffee containing compounds. In conclusion, SCG were found to be a good natural alternative filler for bio‐based NBR composites without a significant change in material properties.Highlights Spent coffee grounds ‐ a sustainable filler in bio‐based NBR composites Both fresh and spent coffee grounds are successful stabilizers Physico‐mechanical, thermal, and dielectric properties are comparable

Basalt fiber reinforced polypropylene to manufacture 3D printed composites

AbstractPolypropylene (PP) is one of the most used polymeric materials worldwide, either as a neat material or as a matrix for composite manufacture employing a molding process. Fused deposition modeling (FDM) 3D printing is an alternative process that offers the potential for manufacturing value‐added products from PP. However, using neat PP for FDM is challenging because 3D‐printed PP warps and shrinks when cooled, and the mechanical properties of PP are poor. PP‐based composites with different fillers (e.g., glass, carbon, and natural fibers) have shown improved properties using FDM processes. An alternative filler for 3D‐printed PP‐based composites is basalt fiber (BF). The objective of this work was to assess the potential and impacts of BF as a filler for BF‐PP composites using FDM processes. PP was compounded with 15, 25, 35, and 45 wt% BF to produce filaments for 3D printing without adding any compatibilizer. Results of rheology studies, morphology, and mechanical and thermal properties of the 3D printed specimens showed that BF positively impacts Young's modulus (E), thermal stability, and dimensional stability of the composite. All composites, when processed at high shear rates (i.e., above 100 1/s), show approximately similar rheological behavior. E is almost doubled in the composite with 25 wt% BF and increased fourfold in the composite with 35 and 45 wt% BF, compared to neat PP. The Izod impact resistance of the formulations containing 35 and 45 wt% BF is ~70% that of neat PP. BF process easily and adequately reinforces PP composites manufactured via FDM.Highlights Neat PP's poor mechanical properties are improved by adding basalt fiber (BF). Up to 45 wt% BF was used to reinforce PP‐based composites. PP‐BF composites are easier to process via DFM compared to neat PP. BF improves PP‐based composite's thermal and dimensional stability.

Impact of reduced sucrose content on processed cheese: Sensory, textural, and storage stability analysis

The present study examines the impact of varying sucrose concentrations (12%, 6%, and 0%) on the sensory qualities and storage stability of processed cheese. Our findings reveal that sucrose is crucial for enhancing color depth, modulating flavor, and improving texture. Specifically, higher sucrose levels impart a caramel color, increase sweetness, and maintain a harmonious balance between salty and sour tastes, thereby mitigating the intensification of unwanted flavors (P < 0.05). Furthermore, sucrose acts as a structural element that bolsters viscoelastic properties and prolongs storage stability; increased sucrose content slows flavor degradation and preserves textural consistency over time. While reductions in sucrose do not significantly compromise the texture of fresh samples (P > 0.05), they necessitate adjustments in flavor profiles. This research highlights the essential role of sucrose in processed cheese and sets the stage for further studies on sugar reduction strategies and the potential use of alternative fillers, marking a significant step forward in the development of processed cheese products.

Recycling of copper tailing as filler material in asphalt paving mastic: A sustainable solution for mining waste recovery

Copper tailings are a category of solid waste discharged after the beneficiation process in mining plants. The significant concern raising stringent environmental issues give impetus to explore the multi-channel utilization of copper tailings in a sustainable manner. Concerning the fact that no study has systematically compared properties of copper tailings filled (CTP) asphalt mastic with conventional limestone filler mastic (LP) at different filler-to-asphalt ratios, multiscale and multi-dimensional comparisons between the characteristics of CTP-asphalt and LP-asphalt mastics were made in this study to thoroughly explore the feasibility and potential of recycling CTP as alternative filler in asphalt materials. Four ratios from 0.3 to 1.2 were used to manufacture asphalt mastics. The in-service pavement performance of asphalt mastics including resistances to rutting, low-temperature cracking and moisture damage was explored. Finally, the environmental and economic perspectives regarding the recycling of copper tailings are analyzed. Results indicate that CTP possesses a rougher surface, a larger specific surface area, and a more uniform pore size distribution than LP, particularly across the mesopores range. These characteristics could promote the adsorption of asphalt on its particle surface, potentially leading to enhanced filler-particle interaction. Regarding pavement performance, CTP-asphalt mastic outperforms LP-asphalt mastic in terms of high-temperature performance. Meanwhile, its low-temperature performance and moisture stability are only limitedly declined with the acceptable performance. Further, heavy metals leaching tests suggest that the risk for the substantial utilization of CTP in paving asphalt is absent. The related outcomes have verified the promising potential of CTP as an alternative candidate to substitute the conventional filler in paving asphalt from comprehensive consideration of in-service performance, and environmental and economic benefits.

Optimizing self-compacting mortars with fillers from sustainable industrial by-products: evaluation of durability parameters

This study investigates the transformative potential of repurposing non-biodegradable industrial by-products, specifically glass, brick, and sanitary ceramic waste, as alternative fillers for self-compacting mortars (SCM). Positioned within the framework of sustainability and enhanced performance, we conduct an in-depth comparative analysis against traditional limestone fillers to ascertain the efficacy of these unconventional materials. Employing a comprehensive methodology, we conduct spreading tests, evaluate heat of hydration, and assess mechanical resistance. Additionally, we delve into key durability parameters, including water-accessible porosity and capillarity, to comprehensively understand the nuanced effects of diverse fillers on the characteristics of the resulting self-compacting mortars. The experimental timeline unfolds through a series of assessments, measuring compressive and tensile strengths at strategic intervals - 2, 7, 28, 90, 270, and 365 days post-application. After 270 days of maturation, our study rigorously examines durability parameters. The findings unequivocally reveal a significant enhancement in SCM performance when incorporating glass, brick, and sanitary ceramic waste as fillers, outperforming conventional limestone fillers. Of notable significance is the consistent superiority of ceramic fillers across a spectrum of metrics. This research significantly contributes to the understanding of sustainable repurposing of industrial by-products in construction. Moreover, it highlights the pivotal role played by ceramic fillers in elevating rheological, mechanical, and durability attributes of self-compacting mortars. Beyond its immediate implications, this study opens new avenues for environmentally responsible and economically viable construction materials, promising further advancements and innovation in the field.

Development and characterizations of jarosite waste reinforced poly(vinyl alcohol) composites: A sustainable approach toward solid waste management

AbstractJarosite, an industrial waste, has the potential to be used as an alternative filler in biocomposites used as packaging material and can replace nondegradable thermoplastic. Such a novel approach of waste management strategy has not been studied till date. In this research work, different weight percentages of jarosite were mixed with poly(vinyl alcohol) (PVA) to fabricate polymer composites with better physico‐chemical, thermal, tensile, and biodegradation properties. The data indicate that a low concentration of jarosite (3 wt.%) improved the tensile strength by 198.7% and the composite showed higher thermal stability by 6.3% than that of the neat PVA. X‐ray diffractogram and transmission electron microscopic analysis revealed a strong interaction between PVA and jarosite. Interestingly, the addition of jarosite reduced the water absorption capacity and thickness swelling of the PVA composite by 58% and 54.7%, respectively. Jarosite‐incorporated composites showed lesser degradation potential (64%) than the control composites (84%) after 60 days under soil burial conditions, indicating that PVA‐jarosite composites have a higher shelf‐life, which is needed for packaging materials. These composites can also be good alternant for thermoplastic used in preparation of cuboid, sealing, and decorative materials. Also, this would be a novel sustainable approach for managing/reducing jarosite waste.Highlights Jarosite was reinforced with PVA to fabricate biocomposites. The maximum tensile strength of the composite was achieved as 45.4 MPa. The thermal stability of mechanically optimized composite is found at 320°C. After 60 days under soil burial, the composite lost 64.8% of its original weight. Developed composites can be good alternant for nondegradable thermoplastic.

Evaluating the Mechanical Performance of Hot and Warm Asphalt Mixtures Utilizing Sulfur Waste as an Alternative Filler

Evaluating the Mechanical Performance of Hot and Warm Asphalt Mixtures Utilizing Sulfur Waste as an Alternative Filler

Evaluating the Mechanical Performance of Hot and Warm Asphalt Mixtures Utilizing Sulfur Waste as an Alternative Filler

Evaluating the Mechanical Performance of Hot and Warm Asphalt Mixtures Utilizing Sulfur Waste as an Alternative Filler

A novel and sustainable rubber composite prepared from electric arc furnace slag as carbon black replacement

Carbon black (CB) is the most widely used reinforcing filler for rubber. Nowadays there are several concerns regarding this traditional petroleum-based filler: on one side its environmental footprint is enormous and its production process is no more sustainable and on the other side its price increases annually. For these reasons, sustainable alternative fillers are being studied. In the present research the main waste of the steel industry, namely the steel slag from electric arc furnace (EAF), is investigated as non-conventional filler for a nitrile butadiene rubber matrix (NBR). The slag has been characterized to ensure its safe reuse as filler according to the heavy metals leaching. The slag filled compounds have been characterized and compared to CB filled compounds, in terms of processability by rheometric parameters, mechanical properties, Payne effect, and physicochemical properties to investigate the filler-matrix interaction. From the obtained results, it was shown that EAF slag-filled NBRs are comparable to CB filled NBRs in terms of crosslink kinetics and, when compared at the same hardness level, are comparable in terms of viscosity, stiffness, and elongation at break, while when compared at the same filler volume fraction are similar in terms of compression set and stress relaxation.

Cellulose-Based Oil Palm Empty Fruit Bunch as an Alternative Filler for Latex Application: A Review

Cellulose is a natural polymer with good properties that have caught researchers' attention to utilize these natural resources' potential. Cellulose also has been widely used as an alternative filler to replace inorganic filler in polymer composites. This review discussed the extraction of cellulose from oil palm empty fruit bunch (OPEFB). This review focused on the OPEFB due to the emergence of palm oil plantations which creates a high amount of biomass, whereas OPEFB is one of the major contributors. The utilization of cellulose application in the polymer focused on alternative fillers in latex application. The postulate crosslink mechanism in latex films is also described to highlight the potential of OPEFB as fillers in latex application. The utilization of OPEFB cellulose has the potential to be explore as bio-fillers with also impact the crosslinks mechanism in latex system which can improved the properties in latex composites.

Effectiveness of Fish Scale‐Derived Collagen as an Alternative Filler Material in the Fabrication of Polyurethane Foam Composites

Effectiveness of Fish Scale‐Derived Collagen as an Alternative Filler Material in the Fabrication of Polyurethane Foam Composites

Chemical and Organoleptic Quality of Beef Sausage by Substitution of Tapioca with Kepok Banana (Musa paradisiaca formatypica) Flour

One of the beef processing is sausage, which is well known in the community. At this time, the need for fast food (ready-to-cook) is increasing. The main ingredient used to produce sausages for stuffing is tapioca flour. The increasing price of tapioca flour is due to the high demand for its use in processed foods, so it is necessary to find alternative fillers that are more affordable. Kepok banana flour (Musa paradisiaca formatypica) has a starch content that is relatively similar to tapioca, so it can be used as an alternative raw material. This study aimed to determine the chemical and organoleptic quality of beef sausage made with Kepok banana flour. This study used a completely randomized design (CRD) consisting of 5 treatments, namely X0 = (control) 0% Kepok banana flour + 20% tapioca; X1 = 5% Kepok banana flour + 15% tapioca; X2 = 10% Kepok banana flour + 10% tapioca; X3 = 15% Kepok banana flour + 5% tapioca; X4 = 20% Kepok banana flour + 0% tapioca, with each treatment consisting of 4 replicates. The variables observed were protein content, moisture content, crude fibre, fat content, ash content and organoleptic of beef sausage. The results showed that the addition of Kepok banana flour in beef sausage processing had a significant effect (P&lt;0.05) on protein content, fat content, moisture content, crude fibre, color, flavour, and aroma, but no significant effect (P&gt;0.05) on ash content and texture of beef sausage. It is concluded that beef sausage made with kepok banana flour as a substitute for tapioca flour produces sausage with better chemical and organoleptic properties than beef sausage made with tapioca flour only. Kepok banana flour can be used as a filler in the production of beef sausage.

Thermo‐mechanical properties of polyethylene composites filled with soapstone waste

AbstractIn this study, soapstone waste originated from craftsmanship activities was used as an alternative filler (0–30 wt%) for a high‐density polyethylene (PE) matrix. The aim of this paper is to understand the effect of the filler particles on crystallinity, thermal stability and thermo‐mechanical properties of this newly developed composite material. Physico‐chemical characterization was performed by x‐ray diffraction (XRD) and Fourier‐transform infrared (FTIR) spectroscopy. Thermogravimetric analysis (TGA), oxidation induction time (OIT) and dynamic mechanical thermal analysis (DMA) were performed to assess the effect of the filler on the themo‐mechanical properties of PE. Thermal stability, measured by TGA, was enhanced, while OIT values reduced with filler content. A significant increase on the storage modulus of the composites (up to 148% in comparison with unfilled PE) was observed and this reinforcing effect was even more prominent at higher temperatures. XRD analysis revealed that the degree of crystallinity improved significantly with soapstone loading, which explains the substantial increase in stiffness observed. Increased crystallinity is also associated with higher strength, reduced residual stress, and better dimensional stability of end products, which can be particularly attractive for pressure pipe applications.

Road performance evaluation of prestressed high-strength concrete pile waste powder as alternative filler in asphalt concrete

As a kind of solid waste, using Prestressed High-Strength Concrete Pile Waste Concrete (PPWC) as the replacement for limestone filler in asphalt concrete can not only reduce the accumulation of PPWC and increase its utilization but also avoid the increased road construction costs and environmental degradation associated with limestone mining. This study aims to investigate the effect of using PPWC filler to replace limestone filler on the road performance of asphalt concrete. Firstly, PPWC was ground into filler particles with a diameter less than 0.075 mm. The particle characteristics such as surface morphology, particle size distribution and chemical composition of PPWC filler and limestone filler were compared. Then, PPWC filler was used to replace limestone filler with different volume fractions to prepare asphalt concrete, and the water damage resistance, high-temperature rutting resistance, low-temperature crack resistance, fatigue resistance and adhesion performance of asphalt concrete were tested. The results showed that PPWC filler has a smaller particle size and rougher surface than limestone filler, and it contains Ca(OH)2 produced by hydration. The addition of PPWC filler can effectively improve the mechanical properties of asphalt concrete without reducing its water damage resistance. PPWC filler can improve the high-temperature rutting resistance and low-temperature crack resistance of asphalt concrete, but reduce its low-temperature fatigue resistance. The low content of PPWC filler will enhance the adhesion between asphalt mortar and aggregate. However, when the content of PPWC filler exceeds 50%, Ca (OH)2 in PPWC will reduce the adhesion between acid asphalt mortar and alkaline basalt aggregate. Therefore, the use of PPWC as filler in asphalt mixtures provides a reliable solution for the sustainable development of road materials.

Mechanical characteristics and regression models of rice husk silica reinforced natural rubber composites

Carbon black and silica fillers have been widely used as reinforcing fillers in tyres and engine mounts. However, both fillers are non-renewable and with REACH legislation in Europe, the USA and elsewhere, where some of these fillers are termed hazardous due to the presence of polyaromatic hydrocarbons (PAHs), there is a need to search for sustainable alternative fillers to wholly or partially replace carbon black as a filler. This research studied rice husks-derived silica (RHS) as a filler in natural rubber (NR). The characteristics of RHS at 50 phr to 90 phr filler loading levels were examined to determine its suitability as a substitute for unsustainable carbon black (N772) fillers used in the rubber industry. Bound rubber content, crosslink density, tensile strength, young modulus, tear strength, shore A hardness, compressive set, and elongation at break were measured. Regression models were generated and the correlation of determination (R2) values was obtained. The RHS composites resulted in maximum tensile strength of 13.20 MPa at 90 phr, tear strength of 119 MPa at 90 phr, shore A hardness of 69 at 90 phr, compressive set of 6.72% at 80 and 90 phr, elongation at break of 453.60% at 80 phr, bound rubber content of 92.14% at 50 phr and crosslink density of 3.87×10-2 mol/cm3 at 70 phr. The results obtained were within the range of those obtained for the carbon black filled composites across various loading levels. The R2 value of mechanical characteristics for the RHS and N772 samples respectively were 50.06% and 62.18% (bound rubber content), 97.62% and 99.85% (tensile strength), 98.44% and 63.97% (tear strength), 89.16 and 97.40% (Shore A hardness), 32.90% and 91.80% (compressive set), a d 50.91% and 46.91% (elongation at break). Rice husk-derived Silica filled natural rubber composites showed favourable mechanical properties and can substitute traditional fillers in tyres, rubber engine mounts, bushings, seals and doormats.