1.1.25 Modern, Smart & Emerging Materials
D&T 2026 — 1.1(c) Product Design Pathway
Materials that respond to the environment or external stimuli
Smart material — a material whose properties change in a controlled, usually reversible way in response to an external stimulus such as heat, light, pressure, moisture or electricity.
Modern material — a material developed through new or improved processes to give properties that traditional materials cannot, such as very high strength for very low weight.
Product designers use smart materials to make products that sense and react without needing electronics, sensors or a power supply. A thermochromic baby spoon “warns” that food is too hot simply because of the pigment it contains.
| Stimulus | Smart material | Response |
|---|---|---|
| Ultraviolet light | Photochromic | Changes colour |
| Temperature | Thermochromic | Changes colour |
| Heat | Shape memory alloy | Returns to a pre-set shape |
| Heat (about 62°C) | Polymorph | Softens so it can be moulded by hand |
| Pressure or friction | Micro-encapsulation | Capsules burst and release their contents |
| Heat | Phase changing material | Absorbs or releases heat as it melts or solidifies |
Photochromic, thermochromic and micro-encapsulation
These are covered in detail in 1.1.2 Modern & Smart Materials. In summary:
- Photochromic materials change colour in UV light and reverse when it is removed — self-darkening spectacle lenses, UV security inks, UV indicator wristbands. (More)
- Thermochromic materials change colour with temperature — baby spoons and bottles, mugs and kettles, battery test strips, food packaging. (More)
- Micro-encapsulation traps tiny droplets inside a coating that bursts when rubbed, pressed or heated — scratch-and-sniff print, fragranced and antibacterial textiles, self-healing materials. (More)
In product design, thermochromic pigments are added to polymers before moulding or printed as inks onto packaging, and thermochromic film is used for simple thermometers. Photochromic pigments can be mixed into polymer resin or printed onto products.
Shape memory materials and polymorph
Shape memory alloy (SMA) — a metal alloy that “remembers” a pre-set shape. It can be deformed when cool, then returns to its original shape when heated.
Nitinol — an alloy of nickel and titanium — is the most widely used SMA. It is used in spectacle frames that spring back after being bent, dental braces that pull teeth into line at body temperature, medical stents that open inside a blood vessel, and thermal safety cut-outs. (More)
Polymorph is a thermoforming polymer supplied as granules that soften at about 62°C in hot water. It can be moulded by hand, sets hard and tough as it cools, and can be reheated and reshaped many times. Designers use it for ergonomic grips, quick prototypes and custom fittings. (More)
Conductive polymers, biometrics and phase changing materials
Conductive polymers
Conductive polymer — a polymer that conducts electricity, unlike most polymers, which are insulators.
- Combines the flexibility and low weight of a polymer with the ability to carry a current.
- Used in flexible circuits, touch-sensitive surfaces, anti-static packaging for electronic components, and wearable technology.
- Conductive inks and threads let circuits be printed onto paper or sewn into fabric, so simple products can light up or respond to touch.
Biometrics
Biometrics identifies a person from a unique biological characteristic — fingerprint, face, iris or voice. Fingerprint sensors are now built into phones, laptops, padlocks, door handles and payment cards. Designers must consider how securely the data is stored, because a fingerprint cannot be changed if it is stolen, and whether the system works for all users. (More)
Phase changing materials (PCM)
Phase changing material (PCM) — a material that absorbs a large amount of heat as it melts and releases it as it solidifies, so it holds a temperature steady.
- Often micro-encapsulated in fabrics, so clothing and bedding absorb heat when the user is warm and release it when they cool down.
- Used in cool packs and food delivery boxes to keep contents at a steady temperature, and in building panels to even out room temperature.
Composite materials
Composite material — two or more different materials combined so that the result has better properties than either material on its own. Usually fibres (for strength) are set in a matrix such as resin (to bind them and spread the load).
| Composite | Made from | Properties | Typical uses |
|---|---|---|---|
| Carbon fibre (carbon fibre reinforced polymer) | Woven carbon fibres set in epoxy resin | Extremely strong and stiff for its weight; corrosion resistant; very expensive; labour-intensive to make | Racing bicycles, Formula 1 cars, aircraft parts, tennis rackets, high-end phone cases |
| Glass reinforced plastic (GRP) | Glass fibres set in polyester resin | Strong, light, waterproof and corrosion resistant; can be moulded into large, complex shapes; much cheaper than carbon fibre | Boat hulls, car body panels, canoes, water slides, roofing |
| Fibreglass | The common name for GRP — also used for the glass fibres themselves | As GRP. The loose glass fibres are also used as a thermal insulator in lofts | As GRP; loft insulation |
How GRP and carbon fibre parts are made: layers of fibre mat or woven cloth are laid into a mould, and resin with a hardener or catalyst is brushed or rolled in (lay-up). When the resin cures, it sets into a rigid, strong shell. The mould surface gives the finished part its smooth face.
Emerging technologies: Bluetooth, Wi-Fi and the Internet of Things
Bluetooth — a short-range wireless technology (typically up to about 10 m) for connecting devices directly to each other using little power, e.g. wireless earbuds to a phone.
Wi-Fi — wireless technology that connects devices to a local network and the internet through a router, with a longer range and faster data transfer than Bluetooth.
Internet of Things (IoT) — everyday products fitted with sensors, processors and wireless connections so they can collect data, communicate with each other and be controlled remotely.
Examples of IoT products: smart thermostats, smart speakers, video doorbells, fitness trackers, smart plugs and lighting, and fridges that track their contents.
| Benefits | Drawbacks |
|---|---|
| Remote control and monitoring from a phone | Security risks — connected devices can be hacked |
| Products adapt to the user, e.g. heating learns a routine | Privacy concerns about the data collected |
| Energy can be saved by switching things off automatically | Products may stop working if the company withdraws support (obsolescence) |
| Data helps manufacturers improve future products | Higher cost and more electronic waste |
AI and machine learning in developing products
Machine learning — a type of artificial intelligence (AI) in which software improves at a task by finding patterns in large amounts of data, rather than following fixed instructions.
AI is changing both how products are designed and what products can do:
- Generative design — the designer sets the constraints (loads, material, size, manufacturing method) and AI-driven CAD produces many possible forms, often lighter and using less material than a human design. (More)
- Testing and simulation — AI can predict how a design will perform and spot weaknesses before a prototype is made.
- Understanding users — machine learning analyses reviews, sales and usage data to show what users want, informing the next product.
- Smarter products — voice assistants, robot vacuum cleaners that map a room, and cameras that recognise faces all use machine learning.
- Manufacturing — AI vision systems inspect products on the production line and predict when machines need maintenance.
Concerns include who owns an AI-generated design, bias in the data AI learns from, privacy, and designers relying on the software instead of their own judgement.
Emerging technology as a driving force in product development
New technologies often lead product development rather than follow it. This is technology push — a new material, component or process makes a new product possible, and the market follows (More).
- Smaller, cheaper components — tiny batteries, sensors and Bluetooth chips made wearable technology such as fitness trackers possible.
- New materials — carbon fibre made lighter, faster bicycles and sports equipment possible; conductive inks allow interactive packaging.
- New processes — 3D printing allows customised products, such as made-to-measure insoles, at low quantities.
- Connectivity — Wi-Fi and the IoT turned ordinary appliances into “smart” products.
Emerging technology also creates obsolescence: when a new technology arrives, existing products can quickly look outdated, which pushes manufacturers to keep developing new versions.