FIBC Liner Types: LDPE, EVOH and Aluminium Barrier Guide

What is an FIBC Liner?

An FIBC liner is a plastic film sleeve inserted into or sewn to the inner surface of a big bag.

Main Functions

• Moisture barrier — Protects hygroscopic products from moisture absorption
• Oxygen barrier — Prevents oxidation and spoilage
• Contamination prevention — Provides isolation from the external environment
• Product containment — Prevents dust escape, ensures clean discharge

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Liner Material Types

1. LDPE (Low-Density Polyethylene)

The most commonly used liner material.

Property	Value
Density	0.910 - 0.940 g/cm³
Flexibility	High
Transparency	High
Moisture Barrier	Medium
Oxygen Barrier	Low
Sealability	Easy

Advantages:

• Economical
• Flexible and easy to apply
• Food contact approval available

Disadvantages:

• Limited oxygen barrier
• Low UV resistance

Suitable Products: Flour, sugar, grain, plastic granules, general purpose

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2. HDPE (High-Density Polyethylene)

A more rigid liner material with chemical resistance.

Property	Value
Density	0.941 - 0.965 g/cm³
Flexibility	Medium
Moisture Barrier	Good
Chemical Resistance	High
Puncture Resistance	High

Advantages:

• Better moisture barrier than LDPE
• High resistance to chemicals
• Mechanical durability

Disadvantages:

• Less flexible
• Sealing challenges

Suitable Products: Chemical powders, fertilizers, industrial minerals

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3. EVOH (Ethylene Vinyl Alcohol)

High-performance material providing superior oxygen and aroma barrier.

Property	Value
Oxygen Barrier	Very High
Aroma Barrier	Very High
Moisture Barrier	Low (standalone)
Structure	Usually multi-layer

Multi-Layer Structures:

• PE/EVOH/PE (standard barrier)
• PA/EVOH/PE (high strength + barrier)
• PA/EVOH/PA (maximum performance)

Advantages:

• Excellent oxygen barrier
• Aroma protection
• Food safety

Disadvantages:

• Moisture sensitivity (single layer)
• High cost
• Requires multi-layer structure

Suitable Products: Coffee, spices, food additives, aroma-sensitive products

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4. PA (Polyamide / Nylon)

Offers a combination of mechanical durability and barrier properties.

Property	Value
Mechanical Strength	Very High
Puncture Resistance	Very High
Oxygen Barrier	High
Moisture Barrier	Medium
Temperature Resistance	High

Advantages:

• Superior mechanical properties
• Good oxygen barrier
• High temperature tolerance

Disadvantages:

• Moisture absorption
• High cost

Suitable Products: Sharp-edged products, high temperature, pharmaceutical raw materials

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5. Aluminium Foil Laminate

Used for maximum barrier performance.

Property	Value
Oxygen Barrier	Absolute (0)
Moisture Barrier	Absolute (0)
Light Barrier	Absolute (0)
UV Barrier	Absolute (0)
Structure	PE/ALU/PE or similar

Advantages:

• Complete barrier (moisture, oxygen, light)
• Longest shelf life
• Metallic protection

Disadvantages:

• Highest cost
• Risk of cracking
• Recycling challenges

Suitable Products: Milk powder, enzymes, vitamins, sensitive pharmaceutical raw materials

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Barrier Performance Comparison

Oxygen Transmission Rate (OTR - cm³/m²·day)

Material	OTR Value
LDPE (50μ)	4000-6000
HDPE (50μ)	1500-2500
PA (25μ)	30-50
EVOH (15μ)	0.5-1.5
Aluminium	0

Water Vapor Transmission Rate (WVTR - g/m²·day)

Material	WVTR Value
LDPE (50μ)	8-15
HDPE (50μ)	4-8
PA (25μ)	80-150
EVOH (15μ)	20-40
Aluminium	0

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Liner Thickness Selection

Application	Recommended Thickness
Standard products	80-100 μ
Heavy loads (>1500 kg)	120-150 μ
Long-term storage	150-200 μ
Moisture-sensitive products	150+ μ with barrier
Maximum protection	200+ μ multi-layer

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Liner Configuration Options

By Attachment Method

1. Loose Liner: Simply inserted into the bag, not attached
2. Tabbed Liner: Attached to bag body with welded tabs
3. Glued Liner: Adhesive bonded to inner surface
4. Sewn Liner: Stitched to bag construction

By Closure Type

1. Open Top: Manual tying or heat sealing after filling
2. Spout Top: Integrated filling spout
3. Form Fit: Shape-matched to bag dimensions

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Industry-Specific Recommendations

Food Industry

→ LDPE for general products → EVOH multi-layer for aroma-sensitive foods → Aluminium laminate for dairy powders → EU 1935/2004 and FDA compliance required

Pharmaceutical Industry

→ PA/EVOH/PE for API protection → Aluminium laminate for maximum stability → Clean room production essential

Chemical Industry

→ HDPE for chemical resistance → Anti-static liners for powder handling → Consider Type C bag compatibility

Agriculture Industry

→ LDPE for seeds and fertilizers → UV-stabilized for outdoor storage → Ventilation requirements if applicable

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Karaca Liner Capabilities

At Karaca, we offer comprehensive liner solutions manufactured in our BRC IoP AA certified facility:

• All material types: LDPE, HDPE, EVOH, PA, Aluminium
• Custom thicknesses: 60-250 microns
• Multi-layer laminates: Tailored barrier properties
• Food-grade certification: EU 1935/2004 compliant

Our technical team can recommend the optimal liner configuration based on your product characteristics, storage conditions, and regulatory requirements.

Request a technical consultation to determine the best liner solution for your application.