For product designers, sourcing managers, and importers new to the plastics industry, navigating the sea of raw material acronyms—such as PP, ABS, PC, PS, and AS—can be a daunting task.
As a custom plastic manufacturer with years of OEM/ODM experience, we know that selecting the correct resin is the single most critical decision in product development. For instance, when manufacturing daily health-related products like a plastic pill organizer or pill box, choosing the wrong material can compromise durability, affect user experience, and even lead to failure in regulatory compliance tests for your target markets.
To help you make informed procurement decisions, this comprehensive plastic raw materials guide breaks down the differences between these five common resins across three vital dimensions: visual appearance, physical properties, and food-grade compliance.

1. PP (Polypropylene) — The Flexible, High-Heat Resistant Safety Standard

• Appearance & Texture: Semitranslucent or milky-white by default, often finished with a matte, soft-touch texture. It exhibits an exceptional flex life. When bent, the plastic shows a characteristic "whitening" stress mark but is extremely difficult to break.
• Physical Properties: PP has the lowest density among common thermoplastics, making it highly lightweight. It is incredibly tough, impact-resistant, and has superior chemical resistance to acids and alkalis. It can withstand temperatures exceeding 120°C (248°F).
• Food-Grade Compliance: PP corresponds to Plastic Recycling Code #5. It is globally recognized as one of the safest food safe plastics and is currently the only plastic approved for microwave heating. It is inherently a BPA free plastic.
• Pill Box Application: Due to its legendary fatigue resistance, PP is the absolute industry-standard material for hinged-lid pill boxes (where the lid and base are connected by a thin, flexible plastic hinge).
• Other Typical Products: Food containers, microwaveable lunch boxes, baby bottles, drinking straws, and automotive bumpers.

2. ABS (Acrylonitrile Butadiene Styrene) — The Rigid, High-Gloss Industrial Performer

• Appearance & Texture: Naturally an opaque ivory or solid white. However, through specialized chemical modification, transparent ABS can also be produced. It yields an exceptionally high-gloss surface finish and is highly receptive to painting, printing, and electroplating.
• Physical Properties: When understanding ABS plastic properties, the key highlights are extreme rigidity, superior impact strength, and excellent scratch resistance. It has low mold shrinkage, ensuring high dimensional stability. Its main limitation is poor UV resistance; prolonged sunlight exposure leads to yellowing and embrittlement.
• Food-Grade Compliance: Standard industrial ABS is not food-safe. While food grade plastic types of ABS do exist for specialized applications, the raw material cost for food-grade ABS is typically double that of standard ABS.
• Pill Box Application: ABS is commonly used to manufacture the outer protective cases of premium multi-compartment pill organizers, providing a robust, impact-resistant shell and a high-end tactile feel.
• Other Typical Products: High-end building blocks (e.g., LEGO), computer keyboard keycaps, luggage suitcases, safety helmets, and home appliance housings.

3. PC (Polycarbonate) — The Shatterproof, Crystal-Clear Crystal Alternative

• Appearance & Texture: Offers optical clarity comparable to glass. It is highly transparent, glossy, and aesthetically premium.
• Physical Properties: Known as "shatterproof glass" or "bulletproof plastic." PC offers unmatched impact resistance among thermoplastics, paired with high temperature resistance (withstanding 120–130°C). However, it is prone to surface scratching.
• Food-Grade Compliance: Is PC plastic safe? This is a critical question for modern buyers. While PC can easily pass US FDA (Food and Drug Administration) food contact tests, its chemical structure contains Bisphenol A (BPA). Consequently, PC cannot pass the strict European BPA-free standards. If your target market is Europe, PC should generally be avoided for food or health-contact products.
• Pill Box Application: Often used for high-end, heavy-duty clear pill cases or transparent viewing windows on premium organizers.
• Other Typical Products: Five-gallon water cooler jugs, sports water bottles, protective eyewear, riot shields, and automotive headlight lenses.

4. PS (Polystyrene) — The Cost-Effective, Rigid Glass Substitute

• Appearance & Texture: Highly transparent and glossy. When tapped, it produces a clear, metallic, high-pitched ringing sound.
• Physical Properties: Extremely cost-effective and easy to process, with high rigidity. Its major drawback is that it is highly brittle and prone to cracking under minor impacts. It has low thermal resistance, starting to deform at 70–80°C.
• Food-Grade Compliance: Corresponds to Plastic Recycling Code #6. It is safe for cold or room-temperature food contact (e.g., yogurt cups) but must never be exposed to hot foods or microwave heating, as high temperatures can cause toxic monomer migration.
• Pill Box Application: Primarily used for ultra-low-cost, disposable, or promotional clear pill containers where durability is not a primary concern.
• Other Typical Products: Disposable plastic cups, CD jewel cases, cosmetic pots, and Styrofoam packaging protective foam.

5. AS / SAN (Acrylonitrile Styrene) — The Upgraded Clear Solution with Chemical Resistance

• Appearance & Texture: Highly transparent, with a premium glassy aesthetic that often carries a very subtle yellowish or blue tint.
• Physical Properties: To answer what is AS plastic—it is a copolymer of styrene and acrylonitrile (often referred to globally as SAN). It is essentially a superior hybrid of PS and ABS. It retains the transparency of PS while incorporating the strength of ABS. It is far more crack-resistant, boasts excellent chemical resistance, and offers slightly better thermal stability than PS.
• Food-Grade Compliance: AS is food-safe, naturally BPA-free, and exhibits excellent chemical stability against acidic ingredients, oils, and detergents at room temperature.
• Pill Box Application: Highly favored for the sliding transparent lids or inner compartments of high-end pill boxes, where visual clarity, structural integrity, and chemical safety are all required.
• Other Typical Products: Blender jars, juicer cups, high-end cosmetic containers, and premium clear tableware.

Quick Sourcing Matrix for B2B Buyers
To assist your engineering and procurement teams in rapid material evaluation, we have structured the key metrics below:

Sourcing Recommendations for US & EU Markets
When customizing health and wellness products like a plastic pill organizer for Western markets, compliance is your baseline. Here are our direct recommendations as an OEM factory:
1. For the European Market: Due to Europe’s strict regulations regarding endocrine disruptors (BPA), we highly recommend choosing AS (SAN) as a clear alternative to PC, or utilizing high-grade PP to guarantee your product seamlessly passes BPA-free certification.
2. For the US Market: PC remains highly popular in America due to its premium crystal-clear appearance and impact resistance, and it easily meets FDA requirements. However, if your brand’s primary USP is "BPA-Free," AS (SAN) is the safer substitute.
3. For Tight Budgets & Integrated Designs: PP is the ultimate B2B workhorse. Its living-hinge capability allows you to mold the lid and body in a single step, saving tooling and assembly costs significantly.
As an export-oriented manufacturer, we assist global brands with material modification, mold design, and mass production compliant with international standards. Contact our technical team today to request a quote or discuss your custom project!