PP Granules- PP Granules suppliers, Types of PP granules, Uses and more

Polypropylene (PP) Granules: An Overview

Polypropylene granules are thermoplastic polymers and are resistant to solvents, chemicals, and other reactants. They are durable and melt at relatively lower temperature than other thermoplastic polymers.

Here’s the kicker:

These granules are the heart and soul of plastic manufacturing. They are used in packaging parts, producing injection molded automotive parts, medical gears, and much more. Whether they are used in injection molding, blow molding, or extrusion of HDPE corrugated pipes, they perform equally well.

Let’s detail out:

Polypropylene polymer is a semi-rigid, lightweight plastic. It belongs to the polyolefin group and is partially crystalline and has non-polar properties. They are formed by the chain polymerization of propylene monomers. It’s not just cost-effective but also one of the lightest plastic material within the commodity plastics category.

The polypropylene story began in 1952 when Robert Banks and J. Paul Hogan of Phillips Petroleum accidently discovered it.

Timeline of Polypropylene development

Source: https://link.springer.com/article/10.1186/s11671-023-03952-z

Today Pp ( Polypropylene) is used in almost every industry from food containers to industrial components.

Some facts about Polypropylene

• Chemical Formula: (C3H6)n
• Structure: Partially crystalline properties. It has both crystalline and amorphous regions

The chemical and physical properties of Polypropylene (PP)

🧪 Polypropylene (PP)( Chemical properties)

Hold on—this is where PP shows off its real strengths!

• Chemical Resistance: To acids, alkalis, organic solvents, lab reagants. It ensures safety from corrosion and harsh environment impacts.
• Hydrolysis Resistance: PP is ideal for use in moist and humid conditions as they are inert to water
• Non-polar nature: Owing to the non-polarity of PP, they don’t interact or react with polar solvents like alcohol or water. They are the best materials for packaging and use for moisture-sensitive products and products which need to be kept safe in humid and rainy conditions
• Sensitivity to Oxygen and UV: PP is highly sensitive to UV and oxygen. So, it requires UV stabilisers, additives for use in sunlight.
• Flammability: PP is combustible and burns but also self-extinguishes as the flame or cause of the burn is removed.

  🔩 Physical Properties of Polypropylene (PP)

• Density of PP:
  ~0.90 g/cm³
  ➡️ Among the lightest of all commodity plastics.
• Melting Point of PP:
  Around 160–170°C. They are apt for hot-fill applications.
• Tensile Strength:
  ~25–40 MPa. They can easily handle impact stress in everyday uses and hence extensively used in rigid packaging for FMCG sectors.
• Flexural Strength: PP is semi-crystalline in nature. That is it doesn’t break
• Hardness: PP has a hardness of R80-R100 and is apt for usage in rugged products
• Impact Resistance: PP is moderate at room temperature and can become brittle in cold. Once injection molded into parts with additives and plasticizers, their impact resistance can be modified several times.
• Transparency: PP is translucent and opaque when high-impact strength is applied or when grinded
• Electrical Insulation: PP has excellent dielectric properties and are used in cable, pipes, and electronic components.

Properties of PP at a glance

(Source: https://www.researchgate.net/figure/Physical-and-Mechanical-Properties-of-Polypropylene-PP_tbl2_298848207)

🏷️ Multiple Grades of Polypropylene (PP)

Source: (https://www.genfollower.com/introduction-of-three-kinds-of-polypropylene-and-their-commonalities-and-differences/)

🔸 1. PP Homopolymer (PPH)

This is the basic form of PP — In this form, polypropylene is made entirely from one type of monomers, propylene monomers through a chain polymerisation reaction

Properties
✅ Strong and lightweight
✅ Rigid than other grades of PP and hence used in rigid packaging in the industry
✅ Highly inert to chemicals

The perfect application
➡️ In textiles, biotechnological and medical syringes, rigid packaging, household goods, and automotive components.

🔸 2. PP Random Copolymer

Let’s get into the structure

It is also formed by polymerisation chain reaction but the monomers in the reaction are not just propylene monomers. They also carry small amounts of ethylene in a random pattern. The addition of ethylene renders more flexibility to it than PP homopolymer.

It has greater transparency and doesn’t brittle down in cooler temperatures easily as PP Homopolymer

Perfect applications
➡️ Food containers where rigid strength is not so much applicable and transparency is preferred. They are equivalently applicable in syringes and transparent , lightweight medical equipments.

🔸 3. PP Block Copolymer

Here the units of ethylene are not added to propylene monomers randomly but in blocks, providing greater toughness to the structure

This increases

• Their impact resistance
• Strength and Longevity

Uses

• Industrial containers
• Bumpers for automotives specifically for heavy trucks and higher load-bearing vehicles
• Rigid pipes to be used in construction

🔸 4. PP Impact Copolymer

In this, upto 65% ethylene is present in the polymer chain of ethylene and propylene.

This makes it

• Tougher at lower temperature
• Ensures higher rigidity and impact resistance

Perfect for:
➡️ Extra strong battery casings, storage bins, pallets, crates, and rugged plastic equipment and goods.

🔸 5. High Melt Strength PP (HMS-PP)

This polymer is made with branching in its molecular structure to increase its melt strength.

They have

• Superb foaming
• High heat resistance
• Great for shaping and molding goods for use in harsh environment.

Applications:

• Thermoformed packaging
• Automotive cushions
• Complex foam parts
• Medical devices that undergo sterilization
• Machines where heat treatment is common

🔸 6. Expanded Polypropylene (EPP)

In this, a blowing agent is mixed with PP. On heating the agent releases gas which on cooling forms foam around the polymer. PP is turned into foam which is lightweight, shockproof, and has heat-dissipation properties.

They make the PP

• Lighter
• With greater impact absorption
• Excellent thermal insulation
• Applications:
• Helmet linings
• Packaging that undergoes impact frequently
• Interiors of a car

🔸 7. PP Terpolymer

Three to tango:
This polymer is made by three momoners ( propylene, ethylene, and butene) in a polymerization chain reaction. They add clarity and softness to PP.

They have

✅ Higher sealing strength than the above polymers
✅ Softer to touch
✅ Higher clarity

• Commonly applications
  Pouch films
• Flexible packaging
• Medical sealing materials.

🔸 8. Bio-Based Polypropylene

This is the best when it comes to getting EPR license from the government. They are made from sugarcane derivatives baggase or mollases or corn.

• They perform equally well as traditional PP
• Reduce environmental footprint massively
• Have biodegradable properties

Applications:

• Green packaging
• Casings for Green industry applications
• Consumer products

✅ Quick Comparison at a Glance

Choosing the right type of PP

You can’t just go and pick any PP from the market. You need to decide the type of application, the strength required of the material, the conditions ( acidic and environmental in which the PP would work)

Properties comparision for usage applications

Why PP Granules are a preferred choice for a wide range of applications industrial and household?

1. Injection Moulding-Friendly

   • Thick to Super thin layers are easily made. Apt for  durable and flexible applications like lids and hinges

2. 360° Twist  or Zero twist without Breaking according to make

   • Yes, you have read right. PP can bear a full twist and can be zero twistable based on the make. This flexibility makes it applicable in wide range of applications in practically all industries

3. Stands tall even on toughest abuse

   • PP resists chemicals, solvents, and moisture like a champion

4. Ultra-Light

   • You can have ultra-light applications

5. Excellent Flexural Strength

   • They have excellent flexural strength to resist wear and tear

Most applicable uses of PP

• Materials Handling: Extra strong pallets and storage bins

• Automotive: Joints, Door panels, battery cases, mirror covers, bumpers and more

• Packaging: From food containers, battery casings, household and industrial packaging to film wraps

• Medical: Injection moulding of multiple medical equipments like syringes equipment, labwares , and more

Processing Techniques

1. Injection Moulding

• Melt Temperature: 200–300°C

• Moulding Temperature: 10–80°C

• Shrinkage: 1.5%–3%

• No pre-drying if stored right

2. Extrusion

• Melt Temp: Between 200–300°C

• Cylinder Temperature: between 180–205°C

• Compression Ratio: 3:1

3. 3D Printing

• Can be done with blends

• 3D printing works best for functional models,and small prototype batches s

4. Other Methods

• Blow-moulding (all types) for PET bottles production and more

(Source:https://robinsonpackaging.com/technical-capabilities/blow-moulding/)

• Compression moulding- Pre-heated material compressed into desired specifications between two heated moulds

• Thermoforming- Transforming raw material into a 3D structure using heat, pressure, and vaccuum

(Source: https://commons.wikimedia.org/wiki/File:Thermoforming_animation.gif)

• Rotational moulding- Creating hollow plastic parts of uniform thickness by rotating a mould carrying plastic resins

(Source: https://prm.co.nz/rotational-moulding/)

💪 PP as compared to other plastics used in injection moulding

🔹 Manufacturer-specific codes for different types of PP available in the Indian market

Some manufacturers use proprietary codes like:

• Reliance: HP550R, RP345S, etc.

• IOCL: IOCL H110MA, IOCL R4220U

• HMEL: HM120N

• ONGC Petro: ONGC H110NA

Examples of product codes for various grades of PP (Polypropylene) granules include:

• Injection Mold Grade Pp: H050MN, H110MA
• PP-Film Grade: K8303, K1010
• General Purpose PP: HP550J, HP510L

Polypropylene granules are often classified as

• IS 10910: Indian Standard for polypropylene intended for food contact applications.
• ASTM D4101: Standard Specification for Polypropylene Plastic established by ASTM.

Cleaning PP products

• Use mild soap and a soft cloth
• Don’t use harsh chemicals
• Tight spots need to be brushed out
• Ink or glue needs to be cleaned immedeately
• Labels on PP products must be treated with Toulene for cleaning
• For tough stains use baking soda paste
• For grease cleaning use a small amount of vinegar

Final Thoughts

Polypropylene granules aren’t just a plastic—they’re a solution. Their adaptability, durability, and sustainability make them a go-to for manufacturers worldwide. And with eco-friendly options on the rise, they’re more future-ready than ever.

Note: Bindal Technopolymer Pvt. Ltd. is currently providing black PP Granules equivalent to virgin and recycled PP Granules for all injection moulding purposes at 80Rs/kg