Shipping delicate vaccines, seafood and biologics at sub zero temperatures can be risky and expensive. A flexible gel dry ice pack solves this by combining dry ice pellets with gel cells that conform to any container. The result is an ultra cold, reusable pack that keeps cargo below –78.5 °C for up to 72 hours. Unlike rigid blocks, flexible packs fit perfectly and cut shipping costs. In this 2025 guide, you’ll learn why flexible gel dry ice packs matter, how they work, and how to choose the right one for your cold chain logistics.
How a flexible gel dry ice pack works and why its design matters – learn about sublimation, gel layers and temperature control.
Comparisons with traditional gel packs and dry ice – explore pros, cons, costs and safety considerations.
Practical tips for using flexible gel dry ice packs – including sizing guidelines and handling protocols.
2025 trends and market insights – discover smart sensors, eco friendly materials and market growth data.
Answers to common questions – from reusability to regulatory compliance.
What makes a flexible gel dry ice pack so powerful?
Flexible gel dry ice packs combine the extreme cold of dry ice with the adaptability of gel cells. Dry ice pellets are sealed inside flexible, reusable gel compartments that conform to any box or pallet, filling gaps and improving temperature contact. Compared with rigid blocks, these packs provide longer cooling durations (24 – 72 hours) and cut wasted space. They also reduce costs because they require less product to achieve the same hold time.
Why hybrid construction matters
Flexible packs contain three layers: a gel sheet layer for even temperature distribution, a dry ice core for ultra cold temperatures, and a protective outer shell. The gel layer slows sublimation so the dry ice lasts longer while preventing cold spots. The outer shell—often polyethylene or non woven fabric—adds puncture resistance and maintains flexibility. This design improves packing efficiency, ensures no liquid residue (dry ice sublimates to gas), and allows the same pack to be reused for multiple shipments.
Benefits at a glance
| Feature | Why it matters | What it means for your shipment |
| Ultra cold temperature (–78.5 °C) | Dry ice maintains deep cold that gel alone can’t | Keeps biologics, vaccines and frozen food below freezing for up to 72 h |
| Flexibility | Gel cells conform to any shape | Fills gaps, improves thermal contact and fits irregular loads |
| Reusable & cost effective | Many packs can be reused after refreezing | Cuts long term costs and reduces waste |
| No water leakage | Dry ice sublimates directly to gas | Prevents wet labels and packaging damage |
| Safe materials | Non toxic gel and protective films | Ensures product and environmental safety |
Practical tips and advice
Choose the right size: Calculate 1–2 lbs of dry ice per 24–48 hours for small shipments and 5–10 lbs for larger loads.
Layer effectively: Spread packs evenly around the product and use the “sandwich” method (bottom and top layers) to ensure uniform cooling.
Ventilation matters: Always leave space for CO₂ gas to escape; do not seal containers airtight.
Pair with insulation: Use high quality insulated boxes or vacuum panels to slow sublimation and extend hold time.
Case study: A vaccine distributor used flexible gel dry ice packs in summer at 35 °C. By pre cooling the container and sandwiching vials between 1 inch thick packs, the vaccines stayed at –20 °C after 48 hours. Without the packs, temperatures would have risen above –10 °C, compromising potency.
How does a flexible gel dry ice pack work? – Science & sublimation
A flexible gel dry ice pack operates through sublimation—the process where solid CO₂ transitions directly to gas. When dry ice sublimates at –78.5 °C, it absorbs large amounts of heat, keeping the surrounding cargo cold. The gel layer slows the sublimation rate and distributes cold evenly, while the outer shell prevents punctures.
Sublimation explained
Heat absorption: Each kilogram of dry ice absorbs roughly 571 kJ of heat during sublimation, far more than water ice melting. This high latent heat capacity keeps goods ultra cold for extended periods.
No residue: Unlike water based ice, dry ice leaves no liquid; it sublimates directly to CO₂ gas, preventing moisture damage and mould.
Uniform cooling: The sheet or pack wraps around the payload, reducing warm corners and hot spots.
Components of a flexible gel dry ice pack
| Component | Role | Real world implication |
| Gel sheet layer | Holds water absorbent polymer; adds flexibility | Distributes cold evenly and reduces sublimation rate |
| Dry ice core | Provides the main cooling power | Maintains temperatures below –78.5 °C |
| Protective shell | PE film or composite fabric | Prevents leaks and punctures, ensuring safe handling |
User-focused guidance
Pre conditioning: Hydrate the gel cells (if applicable) for 15 minutes before freezing.
Complete freeze: Freeze the packs fully to maximize cooling capacity.
Positioning: Place packs around the product and at the bottom for best performance.
Wear protective gear: Dry ice can cause frostbite; gloves and goggles are essential.
Actual example: A biotech firm shipped cryogenic samples using half inch dry ice sheets and high performance coolers. The samples stayed below –70 °C for 24 hours, and no labels were damaged because the packs left no moisture.
Flexible gel dry ice pack vs traditional gel packs – which should you choose?
Comparing a flexible gel dry ice pack with traditional gel ice packs is essential for informed decisions. Gel packs are filled with non toxic refrigerant and freeze at around 0 °C, providing moderate cooling of 2–8 °C. In contrast, flexible gel dry ice packs deliver ultra low temperatures of –78.5 °C and last up to 72 hours.
Pros and cons
Temperature range: Gel packs maintain 2–8 °C and are ideal for fresh foods and pharmaceuticals. Flexible gel dry ice packs provide deep freezing at –78.5 °C for vaccines or ice cream.
Safety: Gel packs are easy to handle and non toxic, while dry ice requires gloves and ventilation due to frostbite and CO₂ gas.
Cost and reuse: Gel packs are reusable and cost effective in the long term; flexible gel dry ice packs also offer reuse but may require replenishing dry ice pellets.
Environmental impact: Gel packs can leak if punctured and may contain polymers that are hard to dispose of. Dry ice sublimation releases CO₂ but avoids liquid waste.
Comparative table
| Refrigerant | Temperature range | Safety & handling | Reusability | Best use cases |
| Gel packs | 2 °C–8 °C | Safe, non toxic, no special handling | Reusable and cost effective | Fresh food, pharma shipments |
| Traditional dry ice | –78.5 °C | Requires gloves, ventilation; hazardous classification | Single use (dry ice sublimates) | Deep freeze goods (ice cream, vaccines) |
| Flexible gel dry ice pack | –78.5 °C with gel moderation | Requires safety gear but easier to handle due to flexible shell | Reusable shell with replaceable dry ice; extended hold time | Biologics, frozen meals, seafood shipments where flexibility and ultra cold temperatures are needed |
Choosing the right solution
Assess your product – Fresh produce or drugs that only require refrigeration? Use standard gel packs. Frozen meals or vaccines? Opt for flexible gel dry ice packs.
Consider shipping duration – For journeys under 48 hours in moderate climates, gel packs are cost effective. Longer or warmer routes may need dry ice.
Safety and regulations – Dry ice shipments must follow hazardous materials rules; gel packs do not. A flexible gel dry ice pack still requires ventilation and labeling but is easier to handle due to its leak proof casing.
Environmental goals – Choose eco friendly materials and reusable packs to reduce waste.
Application scenario: A meal kit service replaced disposable gel packs with flexible gel dry ice packs for 3 day deliveries in rural areas. Customers reported frozen entrées arriving in perfect condition, while the company cut complaints by 15 %.
How to choose and use a flexible gel dry ice pack effectively
Selecting the appropriate flexible gel dry ice pack involves calculating the right quantity, configuring the pack correctly and following safety guidelines.
Sizing your packs
Duration & ambient conditions: For 24–36 hour routes, use 0.5 inch packs on all sides. For 48 hours, increase to 1 inch; for 72 hours, wrap the container fully with 1.25 inch packs.
Weight guidelines: Estimate 1–2 lbs (0.5–1 kg) of dry ice per 24 hours for seafood or frozen meat shipments and 5–10 lbs (2.3–4.5 kg) for pharmaceuticals or biotech samples.
Packing method
Pre cool the container and product before adding the pack.
Layer the pack properly: Use the sandwich method—dry ice at bottom, products in the middle, another layer on top.
Wrap sides if necessary: For extremely sensitive goods, wrap additional side sheets or packs around the payload.
Allow ventilation: Make sure containers have vent holes to let CO₂ gas escape.
Monitor & record: Use IoT sensors or data loggers to track temperature and location. Sensor integration can reduce temperature excursions by 25 %.
Safety and regulations
Wear insulated gloves and avoid direct contact with dry ice to prevent frostbite.
Follow hazardous materials rules: Dry ice is classified as a Class 9 hazardous material (UN 1845). Packages must display the UN number and net weight, with labels at least 100 mm square.
Weight limits: Air transport often limits dry ice to 2.5 kg per package; ground transport allows higher amounts.
Disposal: Let unused dry ice sublimate in a well ventilated area; never dispose of it in plumbing.
Real world tip
A pharmaceutical distributor that switched from gel packs to leak proof dry ice packs saw a 20 % reduction in temperature excursions and 15 % fewer customer complaints. This shows that precise sizing and packaging can improve product integrity and customer satisfaction.
The latest trends and innovations in flexible gel dry ice packs (2025 update)
Trend overview
The cold chain industry is rapidly evolving, integrating smart sensors, AI and eco friendly materials into flexible gel dry ice packs. Dry ice consumption is growing around 5 % per year while CO₂ supply increases only 0.5 %, leading to shortages and price volatility. The global dry ice market was US$1.54 billion in 2024 and is expected to reach US$2.73 billion by 2032, a CAGR of 7.4 %. Meanwhile, the cold chain packaging refrigerants market (including gel packs, foam bricks and PCMs) was US$1.57 billion in 2024, projected to US$1.69 billion in 2025 and US$2.92 billion in 2032.
Latest progress
Smart packaging: Flexible gel dry ice packs now feature IoT sensors for real time temperature and location tracking, reducing spoilage.
Sustainability focus: Manufacturers use biodegradable materials for gel layers and recyclable outer shells. Switching from disposable gel packs to PCMs reduced waste by 60 % in a meal kit company.
AI driven logistics: Machine learning models analyze sensor data to predict temperature excursions and optimize ice quantities.
Hybrid solutions: Shippers mix dry ice with phase change materials (PCMs) to stretch each kilogram of dry ice and reduce costs.
Local CO₂ capture: Producers are building localized dry ice hubs and capturing CO₂ from bioethanol plants to address supply shortages.
Market insights
Regional growth: Europe led the cold chain refrigerants market with a 31.85 % share in 2024. Asia Pacific is the fastest growing region due to expanding pharmaceutical and food industries.
Industry drivers: Food shipping, biologics, vaccine distribution and industrial applications like dry ice blasting fuel demand. Controlled room temperature (CRT) shipments drive adoption of PCMs for 15 °C–25 °C ranges.
Sustainability push: Companies are shifting to renewable CO₂ sources, such as capturing gas from bioethanol fermentation, to reduce carbon footprint.
Frequently Asked Questions
Q1: How long does a flexible gel dry ice pack last?
A properly prepared pack can maintain deep freeze temperatures for 24–72 hours depending on thickness and ambient conditions. For example, a 1.25 inch sheet can protect shipments for 72 hours.
Q2: Can I reuse a flexible gel dry ice pack?
Yes. While the dry ice itself sublimates, the gel cells and outer shell can be refilled with new dry ice and reused multiple times. Always inspect for punctures before reuse.
Q3: How do flexible gel dry ice packs compare with PCMs?
Phase change materials maintain specific temperature bands (–20 °C to +25 °C) and are highly reusable; they’re ideal for CRT shipments. Flexible gel dry ice packs offer ultra cold temperatures but require hazardous materials labels and special handling.
Q4: Are flexible gel dry ice packs safe for food?
Yes. They are made with non toxic materials and do not leak water because dry ice sublimates directly to gas. Always ensure proper ventilation and avoid direct contact with edible products to prevent over freezing.
Q5: What regulations apply to shipping with flexible gel dry ice packs?
Dry ice is regulated as UN 1845, Class 9 hazardous material. Packages must display the UN number and net weight. For air transport, there is often a limit of 2.5 kg per package.
Summary and recommendations
Flexible gel dry ice packs combine the deep freeze power of dry ice with the conformability of gel, providing a reliable cold chain solution for vaccines, frozen foods and biotech samples. They maintain –78.5 °C temperatures for 24–72 hours, reduce shipping space and costs, and prevent moisture damage. Compared with traditional gel packs, they offer longer hold times and better flexibility but require adherence to hazardous materials rules. Emerging trends—like IoT sensors, biodegradable materials and AI driven logistics—will make these packs smarter and more sustainable. When selecting a pack, consider your product’s temperature requirements, route duration and regulatory constraints. Always pre cool containers, size the pack correctly and ensure ventilation for safe transport.
Actionable advice
Assess your temperature needs – Use flexible gel dry ice packs for deep frozen goods; choose gel packs or PCMs for refrigerated or CRT shipments.
Calculate correctly – Estimate 1–2 lbs of dry ice per 24 hours for small loads and 5–10 lbs for pharmaceuticals.
Pre cool and layer – Refrigerate boxes overnight and use the sandwich method for even cooling.
Monitor shipments – Integrate IoT sensors to track temperature and location; adjust packaging based on data.
Adopt sustainable materials – Opt for reusable gel cells and biodegradable films to cut waste.
About Tempk
Tempk is a global innovator in cold chain packaging, supplying flexible gel dry ice packs, gel sheet packs and phase change materials. We develop products that maintain precise temperature control while reducing costs and environmental impact. Our flexible gel dry ice packs use durable, reusable shells and smart sensor integration to optimize shipping. We prioritise sustainability by sourcing recyclable materials and supporting local CO₂ capture initiatives. With decades of experience, we help pharmaceutical, food and biotech clients protect temperature sensitive goods.
Next steps
Contact Tempk’s specialists for a personalized cold chain assessment and learn how flexible gel dry ice packs can improve your logistics. Our experts will recommend the right pack sizes, sensor solutions and sustainable materials for your operations.
