Contact Us

Bike lane on the street

Micro-Mobility

Maximizing the micro

Our materials are creating safer, more efficient drones, e-scooters, mopeds and e-bikes.

Micro-mobility is playing a powerful role in the changing transport landscape of global cities. And Dow is committed to the advancement of cutting-edge automotive technologies that boost performance of every component: headlamps, sensors, bellows, battery packs, seats, tires, charging stations and more.

Working with industry partners and manufacturers, our solutions are enabling the micro mobility revolution.

Micro-Mobility

Explore the Dow solutions that are helping to maximize the possibility of micro-mobility.

Providing riders lightweight, maintenance-free bicycles

Shared bicycles are effective short-distance transportation tools with the advantages of reducing carbon emissions and alleviating traffic congestions. However, the requirements on tires of shared bicycles, such as, riding-comfort, reliability, cost efficiency, and sustainability, are difficult to meet. Air-filled tires are non-reliable with high maintenance costs due to frequent flat tires. Therefore, airless tires have become preferred solutions to shared bicycles today. 

SPECFLEX™ Microcellular Polyurethanes produce micron-sized foam structure that balances comfort, strength, and durability while enables new circular economy for air-less tires. Consequently, SPECFLEX™ provides riders lightweight, maintenance-free, and eco-friendly bicycles reducing carbon emissions and facilitates mobility (Figure 1). 

Bike tire recycle graphic 

Enabling shared-bicycle eco-systems

Figure 1. (A) Scanning Electron Microscopy (SEM) image of Dow SPECFLEX™ Microcellular Polyurethanes, (B) Airless tires made from SPECFLEX™ Microcellular Polyurethanes, (C) The latest shared-bicycle model utilizing Dow SPECFLEX™ Microcellular Polyurethanes, and (D) Basketball playground made from granules of recycled air-less tires using SPECFLEX™ Microcellular Polyurethanes in 2020 (Guangzhou, China). 

What does SPECFLEX™ Microcellular Polyurethanes do?

SPECFLEX™ Microcellular Polyurethanes were molded into 24-inch airless tires with density around 600 kg/m3 (ca. 950 g for each tire) and then mounted onto the wheels of shared bicycles. The air-less tires from SPECFLEX™ Microcellular Polyurethanes eliminate flat-tire risks and bring excellent riding-comfort to riders. Dow SPECFLEX™ Microcellular Polyurethanes are breakthrough products in this field and have been applied to over 3-million bicycles (Figure 2).

Rows of public bicycles

Dow SPECFLEX™ Microcellular Polyurethane tires

Figure 2. (A) Meituan (Mobike) and (B) Hellobike with Dow SPECFLEX™ Microcellular Polyurethane tires.

Different from alternative polyurethane tires that become environmental burdens after service (Figure 3), SPECFLEX™ Microcellular Polyurethanes can be recycled into new applications thanks to patent-pending novel molecular structures (Figure 4). 

Pile of bicycle tires

Airless tires made from problematic materials

Figure 3. Shared bicycles with (A) TPEE airless tires and (B) Dow first-generation microcellular polyurethane air-less tires. (C) Wasted tires with limited recyclability due to inferior material properties caused urgent environment issues. The inserted images in the upper-right corner of panel (A) and (B) illustrate the wear of tires.

Granules chart

Basketball playground made from granules of recycled airless tires

Figure 4. (A) Basketball playground made from granules of recycled SPECFLEX™ Microcellular Polyurethanes air-less tires in 2020 (Guangzhou, China) and (B) illustration of tire granule layer.

How does SPECFLEX™ Microcellular Polyurethanes operate?

SPECFLEX™ Microcellular Polyurethanes apply patent-pending (PCT/CN2019/097011, PCT/CN2019/097014, PCT/CN2020/101771, and PCT/CN2020/102012). Its unique properties, shown in Figure 5, arise from a multi-component system that includes (1) breakthrough ester/ether hybrid structures with unique molecule weight and microstructures, (2) a series of modified isocyanates with variable molecular structure, functionality and molecular weight, (3) a series of standard polyether polyols with variable functionality, molecular weight, structure, and filler content, and (4) additives related to blowing, gelling, appearance, and etc. 

Microcellular Polyurethane 

Formulated systems used to create a microcellular polyurethane material

Figure 5. Formulated systems employing Dow SPECFLEX™ Microcellular Polyurethane technology uses four key components to create a microcellular polyurethane material with excellent tear-resistance, heat stability, internal heat management, abrasion-resistance, weather-ability and recyclability.

Why use SPECFLEX™ Microcellular Polyurethanes?

Dow SPECFLEX™ Microcellular Polyurethanes are advanced microcellular polyurethane foams for airless tires in shared bicycles. It provides superior performance compared to alternative technologies, including;

Enhanced performance

Exceptional performance for superior riding experiences in shared bicycles with safety, comfortableness and durability (Figure 6).

Sustainability

Breakthrough technology enabling recyclable tires of shared bicycles (Figure 7).

Improved processability

10% reduction in rate of defective tires.

Lower costs

20% lower in cost.

Performance comparison

Performance comparison of Dow SPECFLEX™ and products from airless tires

Figure 6. Performance comparison between Dow SPECFLEX™ Microcellular Polyurethanes and products from Dow’s first-generation and competitor for airless tires. Dow SPECFLEX™ Microcellular Polyurethanes show exceptional performance in attributes of tear-resistance, heat-stability, internal heat management, abrasion-resistance, and recyclability, while maintaining good weatherability.

Tensile strength chart

Tensile strength of samples made from tire granules 

Figure 7. Tensile strength of samples made from tire granules of fresh tires and recycled tires from various products using 25 wt.% of Dow standard VORAMER™ MR 1045L as binder. 

Questions about Dow Mobility products and capabilities? Get in touch with a representative.

Stay in the loop with Dow Mobility   

Hear from Dow with our latest innovations and news as we accelerate towards a more resilient, low-carbon future.