衛品行業SAP | 轉向生物基SAP的全球趨勢

 Superabsorbent polymers (SAP) is the working component inside diapers and sanitary towels. These heavy-duty chemicals absorb and retain bodily fluids like blood and urine up to hundreds of times their original weight. 

SAPs revolutionised personal care when they hit the personal hygiene market in the early 1980s. Now, the chemical industry must mount a new wave of innovation, this time targeted at improving product sustainability. Like most polymers, SAPs are not renewable or biodegradable as their basic chemicals are derived from oil. Because single-use applications are common, these non-renewable SAPs contribute massively to air and water pollution. In the US, around 12 billion sanitary pads are disposed of every year while in the UK, diapers account for 2-3 percent of household waste.
sap在20世紀80年代初進入個人衛生用品市場時,徹底改變了個人護理產品市場?,F在,化工行業必須掀起新一輪的創新浪潮,這次的目標是提高產品的可持續性。與大多數聚合物一樣,sap是不能可再生或可生物降解的,因為它們的基本化學成分來自石油。由于一次性應用很普遍,這些不可再生的sap嚴重污染了空氣和水污染。在美國,每年大約有120億塊衛生巾被丟棄,而在英國,尿布占家庭垃圾的2- 3%。
For the last two decades, many companies have tried to lower the carbon footprint of SAP hygiene items with efficiency measures such as decreasing product weight. However, a wholesale shift to biobased SAPs is required to achieve fully renewable, biodegradable, and low carbon items. 
One 2013 study in the International Journal of Life Cycle Assessments suggested that SAPs in disposable diapers contribute most of the product’s total environmental burden, even though absorbents comprise only a fraction of its total weight.  It also found that diapers made from a combination of petrochemical and biobased chemicals brought environmental benefits, including for human toxicity, freshwater eutrophication, and marine ecotoxicity. 
2013年發表在《國際生命周期評估雜志》(International Journal of Life Cycle Assessments)上的一項研究表明,一次性紙尿褲中的sap占了該產品總環境負擔的大部分,盡管吸收劑只占其總重量的一小部分。研究還發現,由石化和生物基化學品組合制成的紙尿褲帶來了環境效益,包括對人體的毒性、淡水富營養化和海洋生態毒性。
Personal hygiene is one application where the physical attributes of a product’s active chemicals are non-negotiable. To capture the absorbents market, renewable SAPs must match or exceed fossil-fuel derived equivalents on performance. Apart from high absorption, the biobased SAP must retain its structure after swelling, have a low soluble content, low price, and be pH neutral upon absorption. Other requirements are that it should be odourless, colourless, and nontoxic for hygiene and comfort.  
Global chemicals companies leading on biobased SAP  
Some major chemicals companies have entered the biobased SAP space over the last few years. These large producers have focused on creating plant-based versions of common base materials for SAP manufacture, such as acrylic acid. One of the most established companies to turn towards biobased SAPs is Nippon Shokubai’s Europe subsidiary, a long-time specialist in conventional SAP and petrochemical acrylic acid manufacture. 
In 2021, Nippon Shokubai Europe advanced its biobased product line by obtaining certification from the ISCC for a bio-based propylene, the substance that goes into making acrylic acid. Their renewable propylene is made from glycerol, commonly sourced from vegetable oils. Nippon Shokubai Europe’s move to biobased acrylic acid forms part of the company’s overarching strategy to achieve carbon neutrality by 2050. It is now developing a biodegradable and recyclable SAP.
2021年,日本Nippon歐洲公司通過獲得ISCC對生物基丙烯(用于制造丙烯酸的物質)的認證,推進了其生物基產品線。他們的可再生丙烯是由甘油制成的,通常來源于植物油。Nippon Shokubai Europe向生物基丙烯酸的轉變是該公司到2050年實現碳中和總體戰略的一部分。該公司目前正在開發一種可生物降解和可回收的SAP 。
Archer Daniels Midland is another global company involved in biobased SAP development. In the early 2000s, the company developed and patented a method for using starch to produce a high-quality SAP. In September 2019, LG Chem and Archer Daniels Midlands announced a joint development agreement to create a bio-based acrylic acid, the leading polymer ingredient in SAP manufacture. The deal will see biotech company AGM supply biobased components to LG Chem, part of LG Chem’s pivot towards the bioplastics segment.  
Archer Daniels Midland是另一家從事生物基SAP開發的國際公司。在21世紀初,該公司開發了一種使用淀粉生產高質量SAP的方法并獲得了專利。2019年9月,LG化學和Archer Daniels Midlands宣布了一項聯合開發協議,以生產生物基丙烯酸,這是SAP制造的主要聚合物成分。根據該協議,生物技術公司AGM將向LG化學供應生物基材料,這是LG化學轉向生物塑料領域的一部分。
A new generation of biobased SAPs hit the market
Some companies have been working with starch and glycerol but green chemicals startups are turning to more unusual feedstocks for biobased polymers requires in SAPs. These second-generation feedstocks and materials tend to offer better product biodegradability on top of renewability.
Ecovia Renewables, a University of Michigan spinoff founded 2014, is pioneering SAP fermentation. Unlike most SAPs on the market, Ecovia’s renewable product is not made from a bio-based acrylic acid. The company uses polyglutamic acid instead, an organic chemical occurs naturally in the silken threads of natto, a fermented soy-based food that is popular in Japan. Ecovia’s ferments polyglutamic acid using the company’s suite of non-GMO microbes. The SAP made from this material has a range of applications. 
Ecovia Renewables是密歇根大學(University of Michigan) 2014年的衍生公司,是SAP發酵的先驅。與市場上的大多數sap不同,Ecovia的可再生產品不是由生物基丙烯酸制成的。該公司使用聚谷氨酸代替,這是一種有機化學物質,天然存在于納豆的絲中,納豆是一種在日本很受歡迎的發酵大豆食品。Ecovia公司使用該公司的非轉基因微生物組合來發酵聚谷氨酸。由這種材料制成的SAP具有廣泛的應用。
Algae is another second-generation SAP feedstock just starting to enter the market. Students at the University of Utah in 2017 developed a sanitary towel containing an brown algae-based SAP. The entire product breaks down within weeks to months. SHERO’s product is a good example of how mixing biomaterials can enhance the performance capabilities of personal hygiene products. In their product, the superabsorbent interior is finished with a final outer layer made from corn that traps moisture inside and prevents leakage. The students were targeting the NGO sector and wanted a low-cost product that could be made easily by communities in developing countries. However, the group plan to sell the product in the US to eco-conscious consumers. SHERO’s biobased sanitary towel is a rare example of a high demand product equally placed to serve both social and environmental goals. 
Bamboo is another candidate for biobased SAP feedstocks which is becoming increasingly popular as a sustainable material. The plant grows back so quickly that cultivated bamboo does not lose much carbon capture potential even if regularly harvested. In 2022, Daye launched an anti-bacterial pad containing a sustainable bamboo absorbent core. It is fully compostable in natural conditions. Like SHERO’s product, its pad combines a biobased SAP with a corn-based material to replace the non-recyclable plastic bodies that make up conventional sanitary items. 
Many more biological substances can be turned into SAPs. Researchers in Advanced Sustainable Systems reported that superabsorbent particles from wheat gluten protein are capable of swelling 4000 % in water and 60% in saline solution, a tenfold performance increase compared to an existing gluten-based materials. It retains as much as 80 percent of the absorbed water, higher than commercial fossil-based SAPs.
更多的生物物質可以轉化為sap。Advanced Sustainable Systems的研究人員報告說,來自小麥面筋蛋白的高吸水性顆粒能夠在水中膨脹4000 %,在鹽水溶液中膨脹60%,與現有的面筋基材料相比,性能提高了10倍。它保留了高達80%的吸收水分,高于商業化石基sap。
Breakthrough in in scaled chitosan and cellulose-based SAPs would be a huge win for the biobased industry. Chitosan is found in shell waste from the seafood industry and cellulose is the most abundant organic compound in nature. The Indian Institute of technology in Madras has already demonstrated a biodegradable SAP using chitosan from seafood waste and citric acid.[1] In 2022, Indian researchers once again advanced the possibilities for biobased SAP by creating a superabsorbent crosslinked hydrogel using cellulose from water hyacinth. 
SAPS are one of the most important consumer chemical classes and are foundational to the global personal hygiene industry. As such, they offer a huge commercial opportunity for bio-enterprises. In 2020, 2.8 million tonnes of SAPs (both biobased and petrochemical) went on the market, with the US and China accounting for 45 percent of global sales in the product. By 2023, total production is expected to go above 3.1 million. The market for biodegradable SAPs is expected to grow at a compound annual growth rate of 8 percent between 2022 and 2030. 
Market prospects are favourable for biobased personal care. Consumers are increasingly sensitive to the environmental impacts of personal care items while the broader biobased polymer market has also been on an upward trajectory. In 2020, for the first time in years, the compound annual growth rate for bio-based polymers was 8 percent, around four points higher than overall growth for polymers.