Discoloration in crepe rubber in Sri Lankan
Rubber Industry
This report is submitted in the Partial fulfillment of the
requirement of the course unit CHE 3210
B.Sc. General Degree in Applied Sciences
Faculty of Applied Science
Rajarata University of Sri Lanka
Mihintale
Name: W.A.D.T.D. Wijesundara
Reg.no: ASB/18/19/117
Index no: 4288
Discoloration in crepe rubber in Sri Lankan Rubber Industry
This is report is submitted in partial fulfilment of the requirement of the course unit CHE
3210
(literature survey / Project)
.………………………………
Signature of the Candidate
W.A.D.T.D. Wijesundara
Registration No. ASB/2018/2019/117
Index No.4288
……………………………............
Supervisor
…………………………………
Prof. H.M.A.M.C. Herath
Mr. A.M. Hafil (C. Chem; M.I. Chem.C) Head/ Department of Chemistry
Senior lecturer
Faculty of Applied Sciences
Department of Chemical sciences
Rajarata University of Sri Lanka
Faculty of Applied Sciences
Mihintale
Rajarata University of Sri Lanka
Date……………………………….
Mihintale
Date……………
Abstract
The Sri Lankan rubber sector, known for its considerable contributions to the worldwide
market, has a recurring challenge: discoloration. This problem has a negative influence on the
appearance and commercial value of crepe rubber goods. This study conducts a thorough
investigation of discoloration in order to propose quiet solutions for reducing its negative
impacts on crepe rubber in the Sri Lankan industrial setting. The fundamental goals of this
research are numerous. First, the study digs into the many phases of crepe rubber manufacture,
identifying key aspects that contribute to the appearance and severity of discoloration. Second
,the study investigates the effect of chemicals used in the latex processing and crepe rubber
production processes, specifically their subtle impact on the occurrence of discoloration.
Third, an in-depth analysis of the chemical composition of crepe rubber and water used in
manufacturing is carried out, with a particular focus on identifying the components that are
susceptible to discoloration. Laboratory experiments and field research are essential parts of
the process. The basis is a comprehensive literature assessment, which includes studies on
rubber chemistry, latex processing techniques, and crepe rubber manufacturing. .Field studies
go across several rubber estates in Sri Lanka, gathering real-world data on latex collecting and
processing. Laboratory tests are meant to imitate various factors that influence discoloration
during crepe rubber manufacture. Initial studies suggest a link between particular latex
components and the development of discoloration in crepe rubber. The examination of
industrial procedures reveals important moments when discoloration tends to worsen.
Chemical examination of processing chemicals used in latex and crepe rubber manufacture
reveals their impact on colour stability. Finally, the purpose of this study is to fill knowledge
gaps in the Sri Lankan rubber sector by investigating discoloration in crepe rubber. By
integrating insights from rubber chemistry, industrial practices, and chemical analysis, the
research hopes to provide practical advice for reducing discoloration. The effects of this
research go beyond the local business, providing vital insights to the worldwide rubber
community.
Acknowledgment
I would like to express my sincere gratitude to all those who contributed to the completion of
this research project on the discoloration of crepe rubber in the Sri Lankan rubber industry.
First and foremost, I extend my heartfelt thanks to Senior Lecturer Mr. A.M. Hafil (C. Chem;
M.I. Chem.C) my research supervisor, for their invaluable guidance, support, and
encouragement throughout this endeavor. Their expertise, mentorship, and constructive
feedback have been instrumental in shaping the direction and methodology of this study.
I am also deeply grateful to the Staff and management of Frocester Rubber Estate - Govinna
Division as well as the workers and professionals in the Sri Lankan rubber industry, for their
cooperation and assistance during the course of this research. Their willingness to share
insights, provide access to facilities, and participate in interviews and discussions have
enriched the study and facilitated data collection.
.I would like to offer special thanks to Mr.S. Bandara Technical Officer , Department of food
chemistry, Faculty of Technology Rajarata University of Sri Lanka, for his assistance in the
laboratory and his dedication to ensuring smooth operation of the experiments. Mr. W.G.W.K.
Wikramasigha and Mr. B.M.M.S. Bandara, Lab Attendants, and Mr. W.M.N. Weerasekera,
Technical Officer, from the Chemistry Laboratory at the Department of Chemical Sciences, for
their technical expertise and assistance in conducting the experiments.
Furthermore, I extend my appreciation to my colleagues and peers for their insightful
discussions, constructive criticism, and encouragement during the research process. Their
diverse perspectives and collective support have been invaluable in refining ideas and
strengthening the research outcomes.
Lastly, I express my deepest gratitude to my family and friends for their unwavering support,
understanding, and encouragement throughout this journey.
This research would not have been possible without the contributions of each and every
individual mentioned above. Thank you for your invaluable support and collaboration.
Content
Abstract…………………………………………………………………………..iii
Acknowledgement………………………………………...……………………..iv
1.0
Introduction………………………………………………..…………………….01
2.0
Methods and Materials………..………………………….….…………………..05
3.0
Results and Calculations…………...……………………………………………08
4.0
Discussion………………………….……………………………………………10
5.0
Conclusion………………………………………………………………………13
6.0
Future directions and Modifications…………………………………………….14
7.0
References………………………………………………………………………15
1.0 Introduction
The rubber plant, Hevea brasiliensis, is a towering symbol of Sri Lanka's agricultural
landscape, with a history closely linked to the growth of the nation's economy (Biswas, 2010).
The history of rubber cultivation in Sri Lanka begins during the British colonial era in the late
19th century. British plantation owners introduced Hevea brasiliensis to the fertile soils of the
island, mainly in the country's wet zones, after realizing the potential of rubber as a profitable
cash crop. A new era in Sri Lanka's agricultural landscape began in 1876 with the planting of
the first rubber seedlings (Biswas, 2010).
The rubber industry in Sri Lanka experienced exponential growth in the early 20th century,
fueled by increasing global demand for natural rubber. Vast expanses of land were converted
into rubber plantations, transforming the lush greenery of the island into a sea of rubber trees.
By the mid-20th century, Sri Lanka had firmly established itself as a major player in the global
rubber market, exporting substantial quantities of raw rubber to destinations worldwide
(Jayasuriya, 2019).
The economic significance of the rubber industry in Sri Lanka cannot be overstated. Beyond
its role as a primary source of foreign exchange earnings, rubber cultivation has played a pivotal
role in rural livelihoods, providing employment opportunities for thousands of Sri Lankans
across the country. (Samarasinghe, 2016).
Furthermore, the rubber industry has aided the expansion of related sectors such as rubber
processing, manufacturing, and exports. Sri Lanka's reputation for manufacturing high-quality
natural rubber has made it a preferred supplier in worldwide markets, charging higher prices
for its products. Furthermore, the industry has driven advances in technology and research
activities aimed at improving efficiency, sustainability, and value addition along the rubber
value chain (Wickramasinghe, 2017).
Latex, the milky fluid extracted from rubber trees, serves as the lifeblood of Sri Lanka's rubber
industry, contributing significantly to the nation's economic prosperity (Biswas, 2010). The
latex industry in Sri Lanka plays a crucial role in processing raw latex into various valuable
products, including crepe rubber, a high-quality rubber known for its elasticity and durability
(Department of Rubber Development, Sri Lanka, 2020).
Crepe rubber holds immense importance in the manufacturing sector, particularly in the
production of footwear, where crepe rubber soles are prized for their superior grip and comfort
(Jayasuriya, 2019).
Additionally, Sri Lanka's rubber industry extends beyond crepe rubber, encompassing a diverse
range of products such as latex gloves, rubber bands, and automotive components
(Samarasinghe, 2016). This multifaceted industry not only drives export earnings but also
supports livelihoods across the country, empowering smallholder farmers and promoting rural
development (Wickramasinghe, 2017).
Crepe rubber, a versatile material prized for its elasticity and durability, plays a crucial role in
various industries, including footwear, automotive, and industrial manufacturing. The
manufacturing process of crepe rubber involves several steps, from the collection of raw latex
to the production of the final product. This essay provides a comprehensive overview of crepe
rubber manufacturing, highlighting key steps and the importance of this process in Sri Lanka's
rubber industry. The process begins with the tapping of rubber trees (Hevea brasiliensis) to
collect latex, the milky fluid that flows from incisions made on the bark of rubber trees. Latex
collection begins with the tapping of rubber trees (Hevea brasiliensis). Tappers make incisions
in the bark of the tree using specialized tools such as tapping knives or hatchets. These incisions
penetrate through the bark and into the cambium layer of the tree, where latex is stored in
specialized cells called laticifers. Once the tree is tapped, latex begins to flow out of the
incisions and into collection cups or containers attached to the tree. The flow of latex is
influenced by various factors, including the time of day, temperature, and weather conditions.
Latex flow is typically highest in the early morning when temperatures are cooler.
Tappers typically visit each tapped tree regularly to collect the latex. They empty the collection
cups into larger containers or buckets, which are then transported to a central collection point.
At the collection point, the latex from multiple trees is pooled together for further processing.
Latex, sourced from rubber trees, consists primarily of water, rubber particles, proteins, lipids,
and carbohydrates. Water serves as a medium for dispersing other components, while rubber
particles provide elasticity. Proteins stabilize the fluid, lipids aid in dispersion, and
carbohydrates support tree growth. Latex also contains trace inorganic compounds.
Once collected, the latex undergoes coagulation, a process that transforms the liquid latex into
a solid form. which is achieved by introducing coagulating agents. These agents cause the latex
particles to aggregate and form solid particles, separating them from the liquid phase. Common
coagulating agents include acids such as formic acid, acetic acid, or synthetic coagulants like
calcium nitrate or aluminum sulfate. The chemical used to coagulate rubber was introduced by
the RRISL (Rubber Research Institute Sri Lanka). After coagulation, the solidified latex is
formed into thin sheets. These sheets are typically rolled or spread out onto flat surfaces to
facilitate drying and further processing. The sheets of coagulated latex are then washed to
remove impurities and excess chemicals used in the coagulation process. The sheets are dried
by using mechanical drying methods.
In rubber processing factories, optimizing drying methods is essential for efficiency and
productivity. One common technique involves using the heat generated by metal tubes carrying
boiling water to dry rubber sheets. The process begins with the heating of water in a boiler or
vessel, generating steam that is then circulated through metal tubes arranged within the drying
area. These tubes, often made of durable materials like steel or copper, act as conduits for the
hot water, transferring its heat energy to the surrounding air and surfaces.
Rubber sheets, having undergone various processing stages, are spread out in single layers on
racks or trays within the drying area. As the hot water flows through the metal tubes, it radiates
heat outward, warming the air and surfaces in proximity. This radiant heat promotes the
evaporation of moisture from the rubber sheets, effectively drying them to the desired moisture
content.
Central to the success of this technique is the careful control of drying conditions. Temperature
and airflow within the drying area are monitored and regulated to ensure uniform drying
without compromising the quality of the rubber sheets. Proper ventilation is essential for
removing moisture-laden air and maintaining optimal drying conditions.
The use of metal tubes for heat transfer offers several advantages. Firstly, it allows for precise
control of drying temperatures, enhancing efficiency and reducing processing times.
Additionally, metal tubes are durable and resistant to corrosion, ensuring long-term reliability
and minimal maintenance requirements. Moreover, this method can be easily integrated into
existing factory setups, minimizing the need for costly equipment upgrades.
The dried sheets of rubber are processed through a creping machine, a crucial step in crepe
rubber manufacturing. The creping machine applies pressure and friction to the rubber sheets,
causing them to stretch and become thinner. This process helps to align the rubber molecules,
improving the strength and elasticity of the final product.
Crepe rubber, renowned for its elasticity and versatility, undergoes a series of chemical
reactions during its manufacturing process, particularly during the crucial step of coagulation.
This process transforms liquid latex, obtained from rubber trees, into solid rubber, laying the
foundation for the production of various rubber products. Understanding the chemical reactions
involved sheds light on the intricacies of crepe rubber manufacturing and underscores its
significance in industrial applications.
At the onset of coagulation, coagulating agents such as formic acid or acetic acid initiate the
denaturation of proteins presents in the latex. This chemical reaction disrupts the native
structure of proteins, causing them to unfold and aggregate. The denaturation process alters the
electrostatic and hydrophobic interactions between protein molecules, facilitating their
coagulation and eventual precipitation from the latex suspension.
Many coagulating agents function by neutralizing the electrostatic charges present on the latex
particles. This neutralization diminishes the repulsive forces between the particles, allowing
them to come closer together and aggregate. As a result, latex particles that were previously
dispersed in the liquid medium begin to coalesce, forming larger aggregates that contribute to
the solidification of the rubber mass.
Certain coagulating agents, particularly those containing metal ions such as calcium or
aluminum, promote the crosslinking of rubber molecules. Crosslinking involves the formation
of chemical bonds between adjacent rubber molecules, resulting in the creation of a network
structure within the rubber mass. This network imparts strength, elasticity, and resilience to the
crepe rubber, enhancing its mechanical properties and making it suitable for a wide range of
applications.
The crepe rubber industry faces ups and downs because rubber prices can change a lot.
Sometimes, other fake rubbers can be cheaper, making it hard for crepe rubber to compete.
Plus, there's worry about hurting the environment when making rubber, like cutting down too
many trees. Crepe rubber comes in all sorts, each with its own special use. There's light-colored
crepe rubber that's super clean and great for things like medical gear and food packaging. Then
there's ribbed smoked sheet (RSS) with its bumpy texture, perfect for making tires and other
strong stuff. And don't forget technically specified rubber (TSR) for special jobs where rubber
needs to be just right.
The color of crepe rubber is a big deal. Some people like the natural, off-white color because
it's real and rustic. Others prefer white crepe rubber, especially for things like medical stuff
because it looks clean and tidy. And there's black crepe rubber too, made by adding special
stuff to make it super strong and resistant to sunlight, great for making tires and heavy-duty
gear. Crepe rubber in its natural state tends to have an off-white or creamy color. This color is
characteristic of unbleached rubber and is often preferred for applications where a natural look
is desired.Some crepe rubber products undergo bleaching processes to achieve a brighter,
whiter appearance. White crepe rubber is favored in applications where cleanliness and
aesthetics are important, such as medical devices and consumer goods.
This research focuses on investigating the occurrence of discoloration patches in crepe rubber
and identifying their underlying causes. Additionally, the quality of production water is
assessed to determine its potential role in contributing to discoloration issues.
2.0 Methods and Materials
2.1 Determine the content elements of the rubber sample
Content elements are determined by the scanning electron microscope EVO 18
Figure 1; figure of scanning electrone microscope
2.2 Determination of pH value of the production water and the used water
pH value of all water samples are determined by using HANNA HI 5522 pH meter.
Figure 2: figure of pH meter
2.3 Determination of conductivity
Conductivity of all water samples are determined by Using Orion 3 star conductivity bench top
conductivity meter.
Figure 3; figure of conductivity meter
2.1 Determine the content elements in the discolored rubber sample
Sample Preparation:
A small piece of the crepe rubber sample was cut using a clean scalpel or razor blade. Then the
sample was put inside the sputter coater for about 5 mins and allowed to goald coat to increase
the conductivity property.
Vacuum Chamber Preparation:
The SEM's vacuum chamber was properly evacuated to create a high vacuum environment.
The chamber pressure was adjusted as per the manufacturer's instructions to optimize imaging
and analysis conditions.
Instrument Setup:
The SEM was turned on and allowed to warm up according to the manufacturer's guidelines.
Sample Imaging:
The sample holder with the mounted crepe rubber sample was placed into the SEM
chamber.The SEM's imaging capabilities were used to obtain high-resolution images of the
sample surface at various magnifications. This helped to identify areas of interest for elemental
analysis.
Elemental Analysis:
The regions of interest on the sample surface were selected for elemental analysis.Energydispersive X-ray spectroscopy (EDS) was performed to analyze the elemental composition of
the selected areas.X-ray spectra were collected from the sample surface by bombarding it with
an electron beam. The X-rays emitted from the sample were characteristic of the elements
present, and their intensities provided quantitative information about their abundance.The
acquired spectra were analyzed using specialized software to identify and quantify the elements
present in the crepe rubber sample.
Reporting:
The results of the elemental analysis were compiled into a comprehensive report, including
images, spectra, and quantitative data.The findings were interpreted in the context of the
research objectives, and conclusions were drawn regarding the elemental composition of the
crepe rubber sample.
Maintenance and Cleanup:
After analysis, the sample holder was carefully removed from the SEM chamber.The SEM
chamber and sample holder were cleaned to remove any debris or contaminants that may affect
future analyses.The SEM was turned off, and proper shutdown procedures were followed as
recommended by the manufacturer.
2.2 Determine the pH value of the production water and the used water
Sampling and Collection:
Production water samples and used water samples were collected from the designated sampling
points using sterile containers to prevent contamination.The samples were labeled with the
date, time, and location of collection for identification purposes.
Preparation of Measurement Equipment:
The pH meter and electrode were calibrated according to manufacturer specifications using
standard buffer solutions.The calibration adjustments were made to ensure accurate pH
measurements.
Sample Analysis:
water samples were poured into clean, dry beakers for analysis.The pH electrode was immersed
into the sample, ensuring it was fully submerged and free from air bubbles.The pH reading was
allowed to stabilize, and the value was recorded once the reading remained constant.
Reporting:
The pH values of water samples were documented in a comprehensive report, including
information on sampling locations, dates, and any relevant observations.
Maintenance and Cleanup:
After analysis, the pH meter and electrode were rinsed with distilled water to remove any
residual sample material.The measurement equipment was properly cleaned and stored
according to manufacturer guidelines to maintain its integrity and performance for future use.
2.3 Determination of conductivity
Sampling and Collection:
Production water and used water samples were collected from designated sampling points
using sterile containers to prevent contamination. The samples were labeled with the date, time,
and location of collection for identification purposes.
Sample Analysis:
Production water and used water samples were transferred into clean, dry beakers for analysis.
The conductivity electrode was immersed into each sample, ensuring it was fully submerged
and free from air bubbles. The conductivity reading was allowed to stabilize, and the value was
recorded once the reading remained constant.
Reporting:
The conductivity values of production water and used water samples were documented in a
comprehensive report, including information on sampling locations, dates, and any relevant
observations.
Maintenance and Cleanup:
After analysis, the conductivity meter and electrode were rinsed with distilled water to remove
any residual sample material. The measurement equipment was properly cleaned and stored
according to manufacturer guidelines to maintain its integrity and performance for future use.
3.0 Results and Calculations
Content elements present in the discolor rubber sample
Figure 4; image of rubber from SEM
Figure 5; the result graph from the SEM machine
Content Elements of Discolor Crepe Rubber Sample
70
60
50
40
30
20
10
0
Carbon
Nitrogen
Elements
Oxygen
Ferrous
Content elements present in the normal rubber sample
Content Elements of Discolor Crepe Rubber Sample
80
70
60
50
40
30
20
10
0
Carbon
Nitrogen
Elements
Oxygen
Ferrous
pH value of production water samples, Mill usage water and production waste water
Average pH value for the Production water and mill usage
water
5.7
5.65
5.6
5.55
5.5
5.45
5.4
5.35
5.3
5.25
5.2
October
November
production water
December
mill usage water
Conductivity value of Production water and mill usage water.
Average Conductivity values for Production water and
the mill usage water
180
160
140
120
100
80
60
40
20
0
October
November
Production water
December
mill usage water
4.0 Discussion
Research investigates the discoloration phenomenon observed in crepe rubber, attributing it to
the presence of ferrous ions. Through scanning electron microscope (SEM) analysis, confirmed
the accumulation of ferrous ions within the discolored areas of the rubber samples, providing
visual evidence of their involvement in the discoloration process.
Furthermore, study examined the conductivity of water used in the manufacturing process,
revealing an increase that suggests the release of ferrous ions from equipment surfaces. This
release of ferrous ions is likely influenced by the acidity of the environment, highlighting the
importance of equipment maintenance and pH control in minimizing discoloration issues in
crepe rubber production.
Overall, those findings underscore the significance of ferrous ion contamination in the
discoloration of crepe rubber and emphasize the need for effective management strategies to
mitigate its impact on product quality.
The coloration of crepe rubber due to the presence of ferric compounds involves complex
mechanisms. Colored compounds may absorb specific wavelengths of light, resulting in
selective absorption and the perception of color. Additionally, the scattering of light by colored
particles alters the material's appearance and hue. The cumulative effect of repeated oxidation
and coloration reactions leads to the gradual accumulation of colored compounds, resulting in
visible discoloration patches in crepe rubber.
Environmental factors, such as temperature, humidity, and UV radiation, can influence the rate
and extent of oxidative reactions in crepe rubber. Furthermore, the presence of other
contaminants in the manufacturing process may exacerbate discoloration issues by promoting
oxidation and the formation of colored compounds. Effective management of environmental
conditions and contaminant levels is crucial for minimizing discoloration and preserving the
quality of crepe rubber products.
the presence of ferrous ions plays a significant role in the discoloration of crepe rubber through
oxidative reactions and the formation of colored compounds. Understanding the mechanisms
by which ferrous ions contribute to discoloration is essential for developing effective strategies
to mitigate this phenomenon. By addressing environmental factors, controlling contaminant
levels, and implementing preventive measures, the quality and aesthetic appeal of crepe rubber
products can be preserved, ensuring their continued relevance and utility across various
industries.
Effective equipment maintenance is essential for optimizing production processes, minimizing
downtime, and ensuring product quality. In the context of crepe rubber production, maintaining
processing machinery is critical for preventing the accumulation of contaminants, including
ferrous ions, which can negatively impact product performance and appearance.
Poorly maintained processing equipment can serve as a reservoir for ferrous contaminants,
which may originate from various sources such as rust, corrosion, or wear and tear of metal
components. Over time, ferrous contaminants can accumulate on equipment surfaces,
particularly in areas exposed to moisture or corrosive substances, such as coagulation tanks or
drying systems.
The presence of ferrous contaminants on processing machinery poses a significant risk of
exacerbating discoloration issues in crepe rubber production. Ferrous ions released from
equipment surfaces can catalyze oxidative reactions in the rubber matrix, leading to the
formation of colored compounds that contribute to discoloration. This phenomenon is
especially pronounced in environments with elevated acidity levels, where ferrous ions are
more readily released from metal surfaces.
Discoloration of crepe rubber not only affects its aesthetic appeal but also compromises its
functional properties and performance. Colored compounds formed as a result of oxidative
reactions can alter the mechanical, thermal, and chemical properties of the rubber, leading to
reduced durability, adhesion, and resilience. Additionally, the presence of discoloration may
deter consumers and impact market acceptance of crepe rubber products.
To mitigate the accumulation of ferrous contaminants and minimize discoloration issues in
crepe rubber production, proactive maintenance strategies must be implemented. This includes
regular inspection, cleaning, and lubrication of processing equipment to prevent rust and
corrosion. Additionally, measures such as pH control, surface coating, and use of corrosionresistant materials can help reduce the release of ferrous ions from equipment surfaces.
Equipment maintenance practices play a critical role in mitigating ferrous contaminants and
minimizing discoloration issues in crepe rubber production. By addressing the root causes of
ferrous ion accumulation on processing machinery, manufacturers can preserve product
quality, enhance operational efficiency, and maintain the integrity of crepe rubber products.
Implementing proactive maintenance measures is essential for ensuring the long-term viability
and competitiveness of the crepe rubber industry.
Ferrous ions (Fe2+) released from equipment surfaces can interact with rubber compounds
through various mechanisms, leading to discoloration. One possible interaction involves the
adsorption of ferrous ions onto the surface of rubber particles, facilitated by electrostatic forces
or chemical bonding with functional groups present in the rubber matrix.
The presence of ferrous ions in the rubber matrix can initiate oxidation reactions, particularly
in environments with elevated levels of oxygen or other oxidizing agents. In the presence of
oxygen molecules, ferrous ions undergo oxidation to form ferric ions (Fe3+), accompanied by
the transfer of electrons. This process generates reactive oxygen species (ROS), such as
superoxide radicals (O2-) and hydroxyl radicals (OH·), which can further react with rubber
compounds.
Oxidative reactions involving ferrous ions and rubber compounds can lead to the formation of
colored compounds, such as ferric oxides and hydroxides. These colored species impart hues
ranging from brown to red, depending on their chemical composition and structural
characteristics. The accumulation of colored compounds within the rubber matrix contributes
to the observed discoloration in crepe rubber products.
The rate and extent of oxidation reactions involving ferrous ions and rubber compounds are
influenced by environmental factors, including pH, temperature, and humidity. In acidic
environments, such as those commonly encountered in rubber processing, ferrous ions are more
prone to oxidation and release from equipment surfaces, exacerbating discoloration issues in
crepe rubber production.
To mitigate the impact of ferrous ion interaction on discoloration in crepe rubber,
manufacturers must implement preventive measures. This includes maintaining proper pH
levels in processing environments, employing corrosion-resistant materials for equipment
construction, and minimizing exposure to oxygen and other oxidizing agents. Additionally, the
use of antioxidants and metal chelating agents may help inhibit oxidation reactions and
preserve the color stability of crepe rubber products.
Despite the conclusions gathered from the research, many limitations must be addressed. First,
the study's sample size may have been insufficient to capture the complete range of
discoloration events in crepe rubber manufacture. Furthermore, the experimental
circumstances used in the study may not accurately reflect the complex and dynamic
surroundings found in industrial settings. Furthermore, the scope of the analysis may have been
limited, concentrating on only the presence of ferrous ions and equipment maintenance
procedures, whereas other factors impacting discolouration were not thoroughly investigated.
Future study might look at a variety of approaches to better understand the interaction between
ferrous ions, equipment maintenance, and discolouration in crepe rubber. For starters, bigger
sample sizes and various manufacturing conditions may allow for a more thorough knowledge
of the components that contribute to discolouration. Furthermore, thorough examinations into
specific chemical processes, such as oxidation reactions catalysed by ferrous ions, might reveal
the mechanisms driving discoloration events.
Furthermore, further investigation into reducing methods, such as the setting up of advanced
machinery maintenance procedures or the use of oxidation inhibitors, is warranted in order to
improve the quality and look of crepe rubber products. Finally, multidisciplinary techniques
combining collaboration among materials scientists, chemists, engineers, and industry
stakeholders might aid in the development of comprehensive solutions to discolouration
difficulties in crepe rubber manufacturing.
The findings of this research have important practical implications for the crepe rubber
business, specially in terms of equipment maintenance routines and quality assurance
processes. Our research provides significant insights that may influence industrial practices
and help to improved production processes by emphasising the significance of ferrous ion
pollution in discolouration concerns, as well as the need of proactive maintenance actions.
5.0 Conclusion



Compared to the normal rubber sample and the discolorrubber sample there is a
competitive arise in ferrous element.
There is a Copetitive arise presence in the conductivity in the mill usage water and the
production water.
Production and mill usage water is normal water that’s pH around 5.
6.0 Future directions and Modifications




Investigate the possible influence of pollutants other than ferrous ions on crepe rubber
discolouration. Conduct extensive research to detect and quantify the presence of
different pollutants and their interactions with rubber compounds.
Conduct extensive structural research to understand the chemical mechanisms behind
discolouration. Use modern analytical techniques, like as spectroscopy and microscopy,
to investigate the creation of coloured compounds and their link to particular pollutants
and environmental factors.
Optimize equipment maintenance practices to reduce ferrous ion contamination and
discolouration in crepe rubber manufacturing. Determine the efficacy of various
cleaning procedures, surface treatments, and corrosion-resistant materials in avoiding
ferrous ion leakage from equipment surfaces.
Investigate the use of modern monitoring technology, such as sensors and predictive
maintenance systems, in crepe rubber manufacturing processes. These systems can give
real-time data on equipment health, enabling proactive maintenance actions to prevent
discolouration and assure product quality.
8.0
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