Main brushes, side brushes and gears rotate for long periods and get tangled with hair. Wear and deformation cause noise and jamming.
Advice · Candidates
Advice
Use POM first for gears and bushings, for low friction and dimensional stability. Use glass-fiber-reinforced PA for heavily loaded spindles. Allow in the design for dimensional changes of PA after moisture absorption.
Robot vacuums and docking stations charge and run unattended. Appliance safety standards set glow-wire requirements for plastic parts carrying electrical connections. Looking only at the UL 94 rating is not enough.
Advice
First identify which plastic parts "support connections carrying more than 0.2 A", then set the GWFI and GWIT targets per the clause; if the material falls short, the standard allows a glow-wire test on the part or a needle-flame test on surrounding parts. Reinforced PBT and PA66 usually reach higher glow-wire temperatures more easily. Test at the actual wall thickness and color.
Docking stations and wet-dry floor cleaners are in long-term contact with hot water and cleaning fluids. PC and PC/ABS may crack under stress and cleaners together. PA absorbs water and changes dimensions.
Advice
Run stress tests with the actual cleaners and service temperature. For parts in long-term contact with hot water, consider PP or hydrolysis-resistant materials first. For transparent water tanks, validate both retained transparency and crack resistance.
Appliance color and gloss are part of brand identity. Top covers, docking stations and accessories come from different batches, and large color differences lead to rejections. Painting adds cost and VOC.
Advice
Color match at the compounding stage, and confirm the color difference limit, light source and gloss. Consider high-gloss mold-in-color materials. Products used by windows need UV resistance.
Kettles, coffee machines and similar products have both food contact parts and electrical parts. Regulations differ by market. The EU has banned BPA in food contact materials, which affects traditional PC water level windows.
Advice
Select materials for food contact parts and non-food-contact parts separately. For food contact parts, prepare compliance documents and migration tests for the target market — China GB 4806 series, EU (EU) No 10/2011 and (EU) 2024/3190, US FDA. Select non-food-contact bases and thermostat brackets by electrical safety requirements.
Food contact parts: food-contact grades are available, with compliance testing supported to GB 4806 and (EU) No 10/2011 requirements, and are provided per project
Material selection for plastic parts in robot vacuums and docks, wet-dry floor cleaners, handheld vacuums, hair dryers, kettles and other kitchen appliances, and washing machines.
80 °C, 4–6 h (desiccant dryer); moisture content 0.05–0.2 % recommended
Melt temperature
280–300 °C; do not exceed the TDS upper limit for flame-retardant grades
Mold temperature
80–110 °C
Why this material
Close to motor heat and vibration; needs stiffness, heat resistance and flame retardancy
Industry overview and trends
Cleaning robots are growing fast
In 2025, about 32.7 million household cleaning robots shipped worldwide, up about 20 % on the previous year. Robot vacuums accounted for about 24.1 million, up about 17 %, or about three quarters. Robot lawn mowers and window-cleaning robots grew faster, and pool cleaning robots are going cordless. Chinese brands hold important positions in several categories.
From indoors to outdoors
Cleaning robots are expanding from indoor floor cleaning to lawn mowing, window cleaning and pool cleaning. Outdoor products bring new material requirements for UV resistance, water resistance and low-temperature impact.
Docking stations keep getting more complex
Auto-emptying, automatic water fill and drain, hot-water mop washing and drying put more water tanks, water paths and heated parts in the dock. Materials must resist hot water and cleaners, and meet the glow-wire requirements for unattended appliances.
Personal care appliances get faster and hotter
High-speed hair dryers have fast motors and hot outlet air. Surrounding plastic parts must withstand heat long-term while staying light and good-looking.
Food contact requirements are stricter
China's new national standard for food-contact plastics, GB 4806.7-2023, has applied since September 2024. EU Regulation (EU) 2024/3190 bans bisphenol A (BPA) in food contact materials, and most transition periods ended in July 2026. This affects the use of PC-type materials in kettles, coffee machines, blenders and similar products.
Recycled content and environmental rules
Home appliance brands commonly set recycled-content targets. Export products must meet RoHS and REACH. The EU is reviewing a universal PFAS restriction proposal under REACH; as of October 2026 it is still a proposal.
In 2025, global shipments of home cleaning robots were about 32.7 million units (about +20 %). Robot vacuums were about 24.1 million units (about +17 %), about three quarters of the total.
Cleaning robots are moving outdoors: lawn mowers, window cleaners and pool cleaners. Outdoor parts need UV, water and low-temperature impact resistance.
Docks now include water tanks, water paths and heaters.
High-speed hair dryers run hotter. Nearby plastic parts need long-term heat resistance.
China's food-contact plastics standard GB 4806.7-2023 took effect in September 2024.
Brands set recycled-content targets.
Part-to-material guide
Full list · 13 parts
This table shows common industry practice for first-round selection. The final choice depends on the applicable standards, the actual wall thickness and validation results (to be verified by GREENPOLYMER).
Large appearance surfaces; must resist scratches and knocks; consistent color
Key requirements
Appearance (high-gloss or matte); impact; low warpage; UV resistance (sun by windows)
Common standards
IEC 60335-2-2; GB 4706.7; ISO 179
GREENPOLYMER grade
GRN-ABS-A110 — high-gloss, mold-in-color; GRN-PCA-T310; GRN-ABS-G110. Obstacle avoidance, docking and LiDAR windows: IR-transmissive black PC is available for sensor and LiDAR windows
Example grade / typical values — to be corrected by GREENPOLYMER
Clean / dirty water tank (robot, dock, wet-dry cleaner)
Typical materials: PP, transparent PC, ABS, PCTG
Why
Water and cleaner resistant; water level often needs to be visible; welding or sealing needed
Key requirements
Hydrolysis resistance; chemical resistance; transparency; seal dimensions; long-term contact with hot water (docking station)
Common standards
ISO 22088 (environmental stress cracking); per your cleaner resistance specification
GREENPOLYMER grade
Transparent window: GRN-PC-L110 (validate for long-term hot water and strong alkaline cleaners); PP for the tank body: Available as a project-based development (non-flame-retardant PP)
Charges unattended; the power section needs flame retardancy and glow-wire performance
Key requirements
V-0; GWFI ≥ 850 °C and GWIT ≥ 775 °C (unattended, carrying connections > 0.2 A; see IEC 60335-1, clause 30.2.3; the applicable clause and product certification requirements prevail); comparative tracking index (CTI)
Direct contact with hot water; must be heat resistant and odor-free; BPA-based PC cannot be used for food contact parts sold in the EU
Key requirements
Food contact compliance (migration); boiling water resistance; no odor; transparency (water level window)
Common standards
GB 4806.1; GB 4806.7-2023; GB 9685; Regulation (EU) No 10/2011; Regulation (EU) 2024/3190 (BPA); FDA 21 CFR 177
GREENPOLYMER grade
Food-contact grades are available, with compliance testing supported to GB 4806 and (EU) No 10/2011 requirements; food-contact grades are provided per project. Note: GRN-PC-L110 is a PC and is not used for EU food contact parts
Example grade / typical values — to be corrected by GREENPOLYMER
Washing machine tub, detergent drawer
Typical materials: Filled PP, PP-GF; PP and ABS for detergent drawers
Why
Resistant to water, detergent and hot water; large parts that must resist deformation
Key requirements
Resistance to hot water and detergent; creep resistance; warpage of large parts; vibration fatigue
Common standards
IEC 60335-2-7; GB 4706.24; ISO 22088
GREENPOLYMER grade
Outer tub: GRN-PP-E510 (flame-retardant glass fiber PP; whether flame retardancy is needed is confirmed per project). Non-flame-retardant filled PP: Available as a project-based development
Example grade / typical values — to be corrected by GREENPOLYMER
Notes
In unattended appliances, insulating material supporting connections that carry more than 0.2 A generally needs GWFI ≥ 850 °C and GWIT ≥ 775 °C (see IEC 60335-1, clause 30.2.3; the applicable clause and product certification requirements prevail). If the material falls short, the standard allows a glow-wire test on the part itself (for example, at 750 °C with flames lasting no more than 2 s); if that is not met, surrounding parts must be rated V-0 or V-1 or pass the needle-flame test (IEC 60695-11-5). The Chinese equivalent is GB 4706.1.
Glow-wire results depend on wall thickness and color; test at the actual wall thickness and color.
Food contact compliance applies to a specific grade and conditions of use (temperature, time, food type); migration tests and a declaration of compliance are needed. Standard engineering plastic grades cannot be used directly for food contact parts. Food-contact grades are available, with compliance testing supported to GB 4806 and (EU) No 10/2011 requirements.
Carbon-fiber-reinforced materials may conduct electricity and cannot be used directly as electrical insulating parts.
GREENPOLYMER grades for home appliances and cleaning
Typical values. Refer to the actual TDS. GWFI, GWIT and CTI data are to be verified by GREENPOLYMER; request test reports per grade.
The grades in the table above are not food-contact grades. Food contact parts: food-contact grades are available, with compliance testing supported to GB 4806 and (EU) No 10/2011 requirements; food-contact grades are provided per project.
GREENPOLYMER does reinforcing, toughening, filling and blending. Formulations can be adjusted to the part's glow-wire, heat resistance, chemical resistance and appearance requirements. Materials marked "Available as a project-based development" in the table can be developed with GREENPOLYMER engineers.
Halogen-free flame retardancy
GREENPOLYMER's flame-retardant technology focuses on halogen-free and fluorine-free solutions. Silicone-based flame-retardant grades do not use PTFE anti-drip agents.
Color matching
The Shenzhen Color Matching Center works to RAL and Pantone numbers and customer color plaques, and can produce high-gloss, matte and metallic effects. Color matching at the compounding and pelletizing stage keeps color more stable from batch to batch.
Recycled grades
Each grade can be customized with recycled content (suffix -R). The recycled share is set per project, with traceability documents. Certificate to be uploaded.
Fast sampling
Free samples of 1–5 kg are available for standard grades, usually shipped in 3–7 working days. Custom formulation samples usually take 1–3 weeks.
Sites
The company headquarters and main plant are in Jiangxi, which is also home to a 3D printing filament industry cluster. GREENPOLYMER also has the Hangzhou Production Base, the Shenzhen Color Matching Center and the Dongguan Development Center. 6,000+ t capacity; 29,000+ m² total plant area.
Patents
8 invention patents.
In-house testing
Test equipment covers melt flow rate, Izod and Charpy impact, horizontal and vertical burning (UL 94 method), heat deflection temperature and Vicat, constant temperature and humidity, UV and xenon-arc weathering, XRF, TGA, DSC, glow-wire, needle flame, comparative tracking index (CTI) and salt spray. In-house tests are for development and quality control and do not replace third-party test reports or UL certification.
Customers and partners
Dyson, Roborock, NARWAL.
3D printing in appliance development
Use
Example
Recommended filament
Appearance models
Appearance reviews of bodies, docking stations and hair dryers
Q1. How do I set glow-wire requirements for appliance parts?
Check two things: whether the appliance is unattended, and whether the part supports connections carrying more than 0.2 A. If so, the usual target is GWFI ≥ 850 °C and GWIT ≥ 775 °C (see IEC 60335-1, clause 30.2.3; the applicable clause and product certification requirements prevail). If the material falls short, the standard allows a glow-wire test on the part itself or a needle-flame test on surrounding parts. Results depend on wall thickness and color.
Q2. The robot vacuum bumper keeps cracking. What should I use?
Bumpers take repeated impacts. Check notched impact and fatigue. Try low-temperature high-impact PC/ABS or high-impact ABS. Also check the radius at snap-fit roots and molding stress. Test low-temperature impact for cold markets.
Q3. Can I still use PC for a kettle water window?
Not for food-contact parts sold in the EU. Regulation (EU) 2024/3190 bans BPA in food-contact materials; most transition periods ended in July 2026. Common alternatives are copolyesters, PP or PPSU. For China, follow GB 4806.7-2023 and related standards. Food-contact grades available; compliance testing to GB 4806 and EU Regulation (EU) No 10/2011 can be arranged.
Q4. How do I choose materials for dock water tanks with hot water and detergents?
Confirm water temperature, detergent chemistry and service life first. Test clear parts for chemical resistance under stress. If transparency is not needed, PP-based materials usually resist water and chemicals better. For electrical parts in wet areas, consider mPPE (often called PPO) or reinforced PBT.