Karen McIntyre , Editor06.01.18
Nonwovens can be made of many fibers and polymers ranging from natural ones like cotton to synthetic materials like polyester and polypropylene. The decision of which material to use to make a nonwoven from depends not just on the end use product but also the process by which is made.
The most popular material used in nonwovens, particularly on the disposable side, is probably polypropylene. This synthetic, petroleum-based material can offer the combination of softness and protection needed in products like diapers, feminine hygiene products and medical items and is used in spunbond and spunmelt nonwovens for topsheet, backsheet and other applications.
Meanwhile, polyester, another synthetic material, is also a popular choice among nonwovens producers but is more commonly used in more durable applications like home furnishings, automotives and carpet materials where softness is not as strong of a concern as strength.
Nonwovens producers and users alike are also showing more interest in the use of natural fibers like cotton and cellulose. These materials not only increase the “green” profile of the final product but they also speak to consumers’ needs for simpler products.
Cotton’s Coming Up
Cotton’s role in the nonwovens industry has seen its share of ups and downs over the year, a trend that has largely had to do with crop yields, pricing and the cost of its key competitors. During the past 12 months, however, the fiber has seen a resurgence that is not just about price.
“Consumers by far and away perceive cotton as the most environmentally friendly fabric there is,” says Janet O’Regan, director of strategic initiatives at Cotton Incorporated, adding she is witnessing a trend toward simpler ingredient lists in personal hygiene products as well as more openness in revealing ingredients lists during the past year. This has benefitted cotton.“It’s soft, it’s natural, it’s skin friendly and consumers trust it,” she says.
Surely these attributes were among the reasons why Procter & Gamble chose to include cotton in its recent natural baby care launch, Pampers Pure diapers and baby wipes.
Introduced this spring, Pampers Pure Protection is being billed by the company as the first-ever diaper and wipe collection made with premium cotton and other thoughtfully selected materials and stylish prints. Pampers Pure was developed by a P&G scientist and mother of twin girls, who couldn’t find an option that had everything she was looking for in baby care products.
Pampers Aqua Pure wipes are designed to give parents Pampers’ highest water content wipe while still delivering outstanding skin protection. The wipes are crafted with carefully-selected ingredients including 99% pure water and a touch of premium cotton, making them safe and soft even on delicate newborn faces, hands and bottoms.
Calling Pampers’ inclusion “huge” for the cotton market, George Hargrove, marketing director of cotton supplier Barnhardt Manufacturing says, “P&G has always been an innovator and their inclusion of cotton is important for consumers by giving them ‘natural’ options in baby care. As a market leader in their categories, one can only believe others will pay attention.”
Already, Johnson & Johnson has hinted at plans to include cotton in its line of restaged baby care products, which will feature more simplified ingredient lists and more natural-oriented ingredients.
“Consumers are more discerning as they become more aware of what their products are made from,” Hargrove adds. “The consumer demand for more natural products began several years ago and has spread more dramatically in recent years as a result of social media.”
Barnhardt’s latest products are actually new generations of prior products that are responses to demands for cleaner cotton that is comparable to synthetics in cleanliness or absent of plant leaf or stem. As Purified Cotton replaces synthetic fibers or extruded films, the consumer is conditioned to expect a clean, white surface which its newest Purified Cotton offerings meet. High Q UltraClean, Organic High Q UltraClean, HyDri UltraClean, and Organic HyDri UltraClean are all products going into the most sensitive areas of hygiene and wipes where performance and purity are paramount.
Barnhardt Purified Cotton meets USP, EP and JP standards for purity that are requirements for consumer and medical devices. Its cotton is purified with safe hydrogen peroxide and is designated as TCF. Barnhardt is able to provide Purified Cotton that is highly absorbent for applications that require absorbency or it can also provide a Purified Cotton for hydrophobic applications.
“Our Purified Cotton products are also recognized for their softness and resilience in nonwoven fabrics,” Hargrove says. “Further consumer perceptions of cotton as a soft, natural and comfortable fiber are confirmed by their long association with cotton in apparel and bath towels, washcloths and sheets. The fact that cotton is naturally hypoallergenic makes it the perfect fiber for sensitive skin. Consumers are also more aware and concerned with the environment throughout the world and recognize cotton’s benefit as a biodegradable and compostable fiber.”
TJ Beall’s TrueCotton unbleached white cotton for carded applications is being used in bedding, mattress and hygiene applications, according to CEO Lawson Gary.
This company has undergone a shift in ownership this spring when Staple Cotton Cooperative Association (Staplcotn) purchased a 50% stake in TJ Beall. The Gary family retained the other 50% stake and Lawson Gary became CEO of the company.
“Staplcotn is excited to partner with Wildwood Gin and Tommy and Lawson Gary. This partnership will beneficial to TJ Beall and support Staplcotn’s core mission of enhancing our members’ incomes,” says Meredith Allen, Staplcotn’s president and CEO. “The Garys have a tremendous amount of expertise and ingenuity in the processing of cotton into quality products for the nonwoven, paper, and traditional textile industries. With global demand for cotton increasing across all cotton industrial uses, TJ Beall’s proximity to our grower-members’ production footprint, and Staplcotn’s position as a leading cotton supplier, tremendous synergies exist. The timing for this partnership is perfect.”
“The Gary and Beall families have partnered for 35 years to innovate and expand new markets for cotton,” says Lawson Gary who became the new CEO of TJ Beall Company upon completion of the transaction. “We are sad to see Julian leave the business but truly appreciate his leaving us in excellent hands with a company that we greatly admire and have trusted to market our farm’s cotton production for many years.”
Tommy Gary, who now serves as COO/CFO of the company adds, “The new partnership with Staplcotn will enable the company to solidify its sourcing needs for cotton as well as continue our quest to innovate new uses for cotton in consumer products.”
Founded in 1921, Staplcotn is the oldest and one of the largest cotton marketing cooperatives in the U.S. It provides a range of services to its members, including cotton marketing, cotton warehousing, and agricultural financing through its lending arm, Stapldiscount. Staplcotn is a 100% producer-owned company with approximately 7000 members in the southeastern U.S. cotton belt.
TJ Beall Company is a manufacturer and supplier of an array of natural cotton fibers for the nonwovens, traditional textiles, technical textiles and paper industries. Currently, TJ Beall produces and supplies recycled cotton fibers, greige premium cotton fibers and an assortment of absorbent cotton fibers.
FiberVisions—Offering a Complete Range in Nonwovens
FiberVisions makes polyolefin staple fibers for nonwoven applications and is the leading supplier of bi-component fibers through its subsidiary, ES FiberVisions. FiberVisions uses proprietary technology and state-of-the-art manufacturing facilities to supply innovative products to customers in industries such as hygiene, textiles, filtration, automotive and construction. With the broadest product portfolio of any polyolefin staple mono and bicomponent fiber company and five own and several partner manufacturing sites around the world, FiberVisions can supply customers with the products they need where they need them.
The company’s fibers are used in nonwovens made by carding, wet lay and airlaid web formation processes and consolidated by thermal bonding, air through bonding, needlepunching and spunlacing.
New offerings to the market from FiberVisions and ES FiberVisions include the development of a broad range of specialty fibers that enables various different features in nonwovens. Each feature can be powerful on their own, but a strong advantage comes with blending; combining the specialty features from various different fibers (mono and bico) to design an optimal solution.
Each individual ES FiberVisions and FiberVisions fiber platform is engineered to enhance specific characteristics in a nonwoven. By utilization of blending, the nonwoven can be custom designed to meet specific requirements, as an optimal blend of various fiber technologies. ES FiberVisions has developed the next generation bi-component staple fibers to deliver superior softness into topsheet and cover stock applications.
The ES FiberVisions new Soft Bico is based on polypropylene/polyethylene bicomponent fibers containing new chemistries to provide built-in softness, durable hydrophilicity and wettability.
Optimum fiber properties are achieved by combining the physical properties of the fiber with its advanced finish technology. This gives outstanding liquid acquisition performance in the nonwoven.
FiberVisions and ES FiberVisions are a part of Indorama Ventures. Indorama, which owns fiber companies including Trevira and soon to be Avgol Industries, an Israel-based manufacturer of spunbond and spunmelt nonwovens. Indorama announced it would acquire a majority stake in Avgol in an effort to increase its presence in the global health and hygiene markets.
Avgol is among the largest manufacturers of nonwovens for hygiene applications in the world, and holds a global market share of 10%. Avgol’s high-performance nonwoven fabrics are used by leading manufacturers of baby diapers, feminine hygiene products and adult incontinence products. Avgol also offers advanced solutions leveraging its proprietary technology such as Avspun and Avsoft hydroentangled spunlaid fabrics, which address consumer requirements, including that of thinner, more discreet, softer and higher performing products.
The acquisition will allow both companies to provide customers with a comprehensive range of products. Indorama Ventures will also be well-positioned to generate future growth in adjacent segments through its strong innovation pipeline, enabling the company to continue to provide compelling value and service to its customers worldwide.
“We are excited by the unique opportunity to bring Avgol into the Indorama Ventures family as it is a major step into expanding our HVA portfolio,” says group CEO Aloke Lohia. “With this acquisition, we are adding a company that has a distinctive position within a compelling segment and with strong growth prospects. Avgol has already made some significant investments to grow the business by expanding its production capacity and geographical footprint and we hope to capture the benefits and help the company reach further heights.”
Avgol’s established client base, complementary capabilities and substantial presence in high-growth markets, together with Indorama Ventures’ global presence, will provide a strong opportunity for creating additional value to best serve all our customers.”
Kelheim Fibres Targets Disinfectant Wipes
Germany’s Kelheim Fibres has tailor made its Danufil QR for use in disinfectant wipes, an area where up until now viscose fibers – in spite of their excellent fluid handling properties – have not been able to establish a foothold. Due to their negative charge, standard viscose fibers bind the so-called “quats” (quaternary ammonium compounds), widely used disinfectant substances that are positively charged, so that they are no longer available for their actual disinfectant purpose. Up to 80% of the effect can be lost this way. Now, Danufil QR resolves the issue by reducing this undesired effect to less than 10%.
With Danufil QR, Kelheim broadens its already multi-faceted range of products, particularly in wipes and hygiene applications.
Another member of Kelheim’s hygiene product family is the flat speciality fiber Viloft, which, with the current release of the newest flushability guideline (GD 4) by INDA/EDANA becomes more important than ever. Viloft short cut fibers enable the production of flushable wet wipes that disintegrate so rapidly in the sewage system that even the significantly stricter requirements of GD 4 can be safely met.
Viloft, like all of Kelheim’s specialty fibers – is made completely of cellulose and is therefore fully biodegradable in a short time, which meets another requirement of the guideline and makes an important contribution to environmental protection.
In April, Kelheim passed a significant milestone, producing its four millionth ton of viscose fibers. This jubilee ton was produced on line two and is a Galaxy fiber, an appropriate coincidence according to production manager Konrad Brunner: “This speciality fiber is made for the tampon industry, one of the most important pillars of our business. This fiber combines our strengths: unique and patented fiber properties meet production conditions that fulfil the strict hygiene requirements of this sensitive final product. It’s not by chance that we have established a world-leading position in this area.”
Considering that about 5000 shirts or even 500,000 tampons can be produced from one ton of viscose fibers alone, the company can get an idea of how many people all over the world have come into contact with viscose fibers from Kelheim, Brunner adds.
Researchers at Virginia Polytechnic University, in Blacksburg, VA, have synthesized a biodegradable alternative to polyolefins using a new catalyst and the polyester polymer, and this breakthrough could eventually have a profound impact on sustainability efforts in polyolefin-based products like disposable baby diapers.
Rong Tong, assistant professor in the Department of Chemical Engineering and affiliated faculty member of Macromolecules Innovation Institute (MII), led the team of researchers, whose findings were recently published in the journal Nature Communications.
Tong says his group has now found a way to create regular stereochemistry with polyesters—a key challenge in polymer chemistry.
“There’s no method available to do this kind of chemistry,” he says. “People have done similar work with polylactide before, but we’ve fundamentally shown that if we control the stereochemistry, the polyesters will have improved physical and chemical properties.”
Tong and his postdoc, Quanyou Feng, combined a new photoredox Ni/Ir catalyst — a surprisingly simple chemical process that uses a household light bulb to start the reaction — with a stereoselective Zn catalyst to initiate the ring-opening polymerization of the O-carboxyanhydride monomer to create these improved polyesters. The monomers can be conveniently polymerized within just a few hours with trace amounts of catalysts. The resulting material has a high molecular weight, thermal stability and crystallinity, and can degrade in basic water solution.
“If you use a regular catalyst, it doesn’t have stereochemistry control, but we found that our catalyst can do that,” Tong said. “In our paper, we demonstrate how to design such stereoselective catalysts and how they help with stereochemistry control.”
O-carboxyanhydrides are made out of amino acids, which are natural organic compounds, so these polyesters would degrade, unlike the current nondegradable polyolefins. In addition, O-carboxyanhydrides can bring different functional groups to the polyester and diversify the polymer’s application. Currently, the FDA has only approved a few polyesters for biomedical application.
After finalizing the synthesis, Tong then worked with Guoliang “Greg” Liu, an assistant professor in the Department of Chemistry and fellow affiliated faculty member with MII, to show that the new polymers had improved properties.
“Dr. Tong’s lab has outstanding catalyst design and polymerization techniques, and we have excellent characterization and processing skillsets, so it’s natural for us to work together,” Liu said. “Controlling and proving tacticity is not a trivial process. Using differential scanning calorimetry and nuclear magnetic resonance, we provide strong evidence for the structure and properties that we’re going for.”
Developing these polyesters into applications is still down the line, but Liu said for now this is a significant advancement for materials research.
“This polyester synthesis that controls the tacticity can provide a new library of polymer materials that we haven’t had before,” Liu said.
This piece of innovative chemistry has Tong and Liu excited for a future that degradable and green plastics can be produced to replace today’s petroleum plastics that persist in landfills and oceans for decades or centuries.
Tong mentioned that this new polymer synthesis technology has been demonstrated only at the academic lab scale. There is still much work to be done to characterize these functional materials and perfect the patent-pending synthesis scale-up process.
“It would be our dream to see these degradable polyesters materialize in the marketplace, for both the plastic industry and biomedical application,” Tong said.
Tong’s team also include Yongliang Zhong, a chemical engineering Ph.D. student; Dong Guo, a chemistry student working in Liu’s lab; and the collaborator Linghai Xie, a professor at Nanjing University of Posts and Telecommunications in China, who helped on the computation studies to elucidate the catalyst stereoselectivity mechanism.
The research was supported by grants from the American Chemical Society Petroleum Research Fund and start-up funding for Tong from Virginia Tech.
The most popular material used in nonwovens, particularly on the disposable side, is probably polypropylene. This synthetic, petroleum-based material can offer the combination of softness and protection needed in products like diapers, feminine hygiene products and medical items and is used in spunbond and spunmelt nonwovens for topsheet, backsheet and other applications.
Meanwhile, polyester, another synthetic material, is also a popular choice among nonwovens producers but is more commonly used in more durable applications like home furnishings, automotives and carpet materials where softness is not as strong of a concern as strength.
Nonwovens producers and users alike are also showing more interest in the use of natural fibers like cotton and cellulose. These materials not only increase the “green” profile of the final product but they also speak to consumers’ needs for simpler products.
Cotton’s Coming Up
Cotton’s role in the nonwovens industry has seen its share of ups and downs over the year, a trend that has largely had to do with crop yields, pricing and the cost of its key competitors. During the past 12 months, however, the fiber has seen a resurgence that is not just about price.
“Consumers by far and away perceive cotton as the most environmentally friendly fabric there is,” says Janet O’Regan, director of strategic initiatives at Cotton Incorporated, adding she is witnessing a trend toward simpler ingredient lists in personal hygiene products as well as more openness in revealing ingredients lists during the past year. This has benefitted cotton.“It’s soft, it’s natural, it’s skin friendly and consumers trust it,” she says.
Surely these attributes were among the reasons why Procter & Gamble chose to include cotton in its recent natural baby care launch, Pampers Pure diapers and baby wipes.
Introduced this spring, Pampers Pure Protection is being billed by the company as the first-ever diaper and wipe collection made with premium cotton and other thoughtfully selected materials and stylish prints. Pampers Pure was developed by a P&G scientist and mother of twin girls, who couldn’t find an option that had everything she was looking for in baby care products.
Pampers Aqua Pure wipes are designed to give parents Pampers’ highest water content wipe while still delivering outstanding skin protection. The wipes are crafted with carefully-selected ingredients including 99% pure water and a touch of premium cotton, making them safe and soft even on delicate newborn faces, hands and bottoms.
Calling Pampers’ inclusion “huge” for the cotton market, George Hargrove, marketing director of cotton supplier Barnhardt Manufacturing says, “P&G has always been an innovator and their inclusion of cotton is important for consumers by giving them ‘natural’ options in baby care. As a market leader in their categories, one can only believe others will pay attention.”
Already, Johnson & Johnson has hinted at plans to include cotton in its line of restaged baby care products, which will feature more simplified ingredient lists and more natural-oriented ingredients.
“Consumers are more discerning as they become more aware of what their products are made from,” Hargrove adds. “The consumer demand for more natural products began several years ago and has spread more dramatically in recent years as a result of social media.”
Barnhardt’s latest products are actually new generations of prior products that are responses to demands for cleaner cotton that is comparable to synthetics in cleanliness or absent of plant leaf or stem. As Purified Cotton replaces synthetic fibers or extruded films, the consumer is conditioned to expect a clean, white surface which its newest Purified Cotton offerings meet. High Q UltraClean, Organic High Q UltraClean, HyDri UltraClean, and Organic HyDri UltraClean are all products going into the most sensitive areas of hygiene and wipes where performance and purity are paramount.
Barnhardt Purified Cotton meets USP, EP and JP standards for purity that are requirements for consumer and medical devices. Its cotton is purified with safe hydrogen peroxide and is designated as TCF. Barnhardt is able to provide Purified Cotton that is highly absorbent for applications that require absorbency or it can also provide a Purified Cotton for hydrophobic applications.
“Our Purified Cotton products are also recognized for their softness and resilience in nonwoven fabrics,” Hargrove says. “Further consumer perceptions of cotton as a soft, natural and comfortable fiber are confirmed by their long association with cotton in apparel and bath towels, washcloths and sheets. The fact that cotton is naturally hypoallergenic makes it the perfect fiber for sensitive skin. Consumers are also more aware and concerned with the environment throughout the world and recognize cotton’s benefit as a biodegradable and compostable fiber.”
TJ Beall’s TrueCotton unbleached white cotton for carded applications is being used in bedding, mattress and hygiene applications, according to CEO Lawson Gary.
This company has undergone a shift in ownership this spring when Staple Cotton Cooperative Association (Staplcotn) purchased a 50% stake in TJ Beall. The Gary family retained the other 50% stake and Lawson Gary became CEO of the company.
“Staplcotn is excited to partner with Wildwood Gin and Tommy and Lawson Gary. This partnership will beneficial to TJ Beall and support Staplcotn’s core mission of enhancing our members’ incomes,” says Meredith Allen, Staplcotn’s president and CEO. “The Garys have a tremendous amount of expertise and ingenuity in the processing of cotton into quality products for the nonwoven, paper, and traditional textile industries. With global demand for cotton increasing across all cotton industrial uses, TJ Beall’s proximity to our grower-members’ production footprint, and Staplcotn’s position as a leading cotton supplier, tremendous synergies exist. The timing for this partnership is perfect.”
“The Gary and Beall families have partnered for 35 years to innovate and expand new markets for cotton,” says Lawson Gary who became the new CEO of TJ Beall Company upon completion of the transaction. “We are sad to see Julian leave the business but truly appreciate his leaving us in excellent hands with a company that we greatly admire and have trusted to market our farm’s cotton production for many years.”
Tommy Gary, who now serves as COO/CFO of the company adds, “The new partnership with Staplcotn will enable the company to solidify its sourcing needs for cotton as well as continue our quest to innovate new uses for cotton in consumer products.”
Founded in 1921, Staplcotn is the oldest and one of the largest cotton marketing cooperatives in the U.S. It provides a range of services to its members, including cotton marketing, cotton warehousing, and agricultural financing through its lending arm, Stapldiscount. Staplcotn is a 100% producer-owned company with approximately 7000 members in the southeastern U.S. cotton belt.
TJ Beall Company is a manufacturer and supplier of an array of natural cotton fibers for the nonwovens, traditional textiles, technical textiles and paper industries. Currently, TJ Beall produces and supplies recycled cotton fibers, greige premium cotton fibers and an assortment of absorbent cotton fibers.
FiberVisions—Offering a Complete Range in Nonwovens
FiberVisions makes polyolefin staple fibers for nonwoven applications and is the leading supplier of bi-component fibers through its subsidiary, ES FiberVisions. FiberVisions uses proprietary technology and state-of-the-art manufacturing facilities to supply innovative products to customers in industries such as hygiene, textiles, filtration, automotive and construction. With the broadest product portfolio of any polyolefin staple mono and bicomponent fiber company and five own and several partner manufacturing sites around the world, FiberVisions can supply customers with the products they need where they need them.
The company’s fibers are used in nonwovens made by carding, wet lay and airlaid web formation processes and consolidated by thermal bonding, air through bonding, needlepunching and spunlacing.
New offerings to the market from FiberVisions and ES FiberVisions include the development of a broad range of specialty fibers that enables various different features in nonwovens. Each feature can be powerful on their own, but a strong advantage comes with blending; combining the specialty features from various different fibers (mono and bico) to design an optimal solution.
Each individual ES FiberVisions and FiberVisions fiber platform is engineered to enhance specific characteristics in a nonwoven. By utilization of blending, the nonwoven can be custom designed to meet specific requirements, as an optimal blend of various fiber technologies. ES FiberVisions has developed the next generation bi-component staple fibers to deliver superior softness into topsheet and cover stock applications.
The ES FiberVisions new Soft Bico is based on polypropylene/polyethylene bicomponent fibers containing new chemistries to provide built-in softness, durable hydrophilicity and wettability.
Optimum fiber properties are achieved by combining the physical properties of the fiber with its advanced finish technology. This gives outstanding liquid acquisition performance in the nonwoven.
FiberVisions and ES FiberVisions are a part of Indorama Ventures. Indorama, which owns fiber companies including Trevira and soon to be Avgol Industries, an Israel-based manufacturer of spunbond and spunmelt nonwovens. Indorama announced it would acquire a majority stake in Avgol in an effort to increase its presence in the global health and hygiene markets.
Avgol is among the largest manufacturers of nonwovens for hygiene applications in the world, and holds a global market share of 10%. Avgol’s high-performance nonwoven fabrics are used by leading manufacturers of baby diapers, feminine hygiene products and adult incontinence products. Avgol also offers advanced solutions leveraging its proprietary technology such as Avspun and Avsoft hydroentangled spunlaid fabrics, which address consumer requirements, including that of thinner, more discreet, softer and higher performing products.
The acquisition will allow both companies to provide customers with a comprehensive range of products. Indorama Ventures will also be well-positioned to generate future growth in adjacent segments through its strong innovation pipeline, enabling the company to continue to provide compelling value and service to its customers worldwide.
“We are excited by the unique opportunity to bring Avgol into the Indorama Ventures family as it is a major step into expanding our HVA portfolio,” says group CEO Aloke Lohia. “With this acquisition, we are adding a company that has a distinctive position within a compelling segment and with strong growth prospects. Avgol has already made some significant investments to grow the business by expanding its production capacity and geographical footprint and we hope to capture the benefits and help the company reach further heights.”
Avgol’s established client base, complementary capabilities and substantial presence in high-growth markets, together with Indorama Ventures’ global presence, will provide a strong opportunity for creating additional value to best serve all our customers.”
Kelheim Fibres Targets Disinfectant Wipes
Germany’s Kelheim Fibres has tailor made its Danufil QR for use in disinfectant wipes, an area where up until now viscose fibers – in spite of their excellent fluid handling properties – have not been able to establish a foothold. Due to their negative charge, standard viscose fibers bind the so-called “quats” (quaternary ammonium compounds), widely used disinfectant substances that are positively charged, so that they are no longer available for their actual disinfectant purpose. Up to 80% of the effect can be lost this way. Now, Danufil QR resolves the issue by reducing this undesired effect to less than 10%.
With Danufil QR, Kelheim broadens its already multi-faceted range of products, particularly in wipes and hygiene applications.
Another member of Kelheim’s hygiene product family is the flat speciality fiber Viloft, which, with the current release of the newest flushability guideline (GD 4) by INDA/EDANA becomes more important than ever. Viloft short cut fibers enable the production of flushable wet wipes that disintegrate so rapidly in the sewage system that even the significantly stricter requirements of GD 4 can be safely met.
Viloft, like all of Kelheim’s specialty fibers – is made completely of cellulose and is therefore fully biodegradable in a short time, which meets another requirement of the guideline and makes an important contribution to environmental protection.
In April, Kelheim passed a significant milestone, producing its four millionth ton of viscose fibers. This jubilee ton was produced on line two and is a Galaxy fiber, an appropriate coincidence according to production manager Konrad Brunner: “This speciality fiber is made for the tampon industry, one of the most important pillars of our business. This fiber combines our strengths: unique and patented fiber properties meet production conditions that fulfil the strict hygiene requirements of this sensitive final product. It’s not by chance that we have established a world-leading position in this area.”
Considering that about 5000 shirts or even 500,000 tampons can be produced from one ton of viscose fibers alone, the company can get an idea of how many people all over the world have come into contact with viscose fibers from Kelheim, Brunner adds.
Researchers at Virginia Polytechnic University, in Blacksburg, VA, have synthesized a biodegradable alternative to polyolefins using a new catalyst and the polyester polymer, and this breakthrough could eventually have a profound impact on sustainability efforts in polyolefin-based products like disposable baby diapers.
Rong Tong, assistant professor in the Department of Chemical Engineering and affiliated faculty member of Macromolecules Innovation Institute (MII), led the team of researchers, whose findings were recently published in the journal Nature Communications.
Tong says his group has now found a way to create regular stereochemistry with polyesters—a key challenge in polymer chemistry.
“There’s no method available to do this kind of chemistry,” he says. “People have done similar work with polylactide before, but we’ve fundamentally shown that if we control the stereochemistry, the polyesters will have improved physical and chemical properties.”
Tong and his postdoc, Quanyou Feng, combined a new photoredox Ni/Ir catalyst — a surprisingly simple chemical process that uses a household light bulb to start the reaction — with a stereoselective Zn catalyst to initiate the ring-opening polymerization of the O-carboxyanhydride monomer to create these improved polyesters. The monomers can be conveniently polymerized within just a few hours with trace amounts of catalysts. The resulting material has a high molecular weight, thermal stability and crystallinity, and can degrade in basic water solution.
“If you use a regular catalyst, it doesn’t have stereochemistry control, but we found that our catalyst can do that,” Tong said. “In our paper, we demonstrate how to design such stereoselective catalysts and how they help with stereochemistry control.”
O-carboxyanhydrides are made out of amino acids, which are natural organic compounds, so these polyesters would degrade, unlike the current nondegradable polyolefins. In addition, O-carboxyanhydrides can bring different functional groups to the polyester and diversify the polymer’s application. Currently, the FDA has only approved a few polyesters for biomedical application.
After finalizing the synthesis, Tong then worked with Guoliang “Greg” Liu, an assistant professor in the Department of Chemistry and fellow affiliated faculty member with MII, to show that the new polymers had improved properties.
“Dr. Tong’s lab has outstanding catalyst design and polymerization techniques, and we have excellent characterization and processing skillsets, so it’s natural for us to work together,” Liu said. “Controlling and proving tacticity is not a trivial process. Using differential scanning calorimetry and nuclear magnetic resonance, we provide strong evidence for the structure and properties that we’re going for.”
Developing these polyesters into applications is still down the line, but Liu said for now this is a significant advancement for materials research.
“This polyester synthesis that controls the tacticity can provide a new library of polymer materials that we haven’t had before,” Liu said.
This piece of innovative chemistry has Tong and Liu excited for a future that degradable and green plastics can be produced to replace today’s petroleum plastics that persist in landfills and oceans for decades or centuries.
Tong mentioned that this new polymer synthesis technology has been demonstrated only at the academic lab scale. There is still much work to be done to characterize these functional materials and perfect the patent-pending synthesis scale-up process.
“It would be our dream to see these degradable polyesters materialize in the marketplace, for both the plastic industry and biomedical application,” Tong said.
Tong’s team also include Yongliang Zhong, a chemical engineering Ph.D. student; Dong Guo, a chemistry student working in Liu’s lab; and the collaborator Linghai Xie, a professor at Nanjing University of Posts and Telecommunications in China, who helped on the computation studies to elucidate the catalyst stereoselectivity mechanism.
The research was supported by grants from the American Chemical Society Petroleum Research Fund and start-up funding for Tong from Virginia Tech.
