Multi-Layer Plastic (MLP) Pouches with Caps — A Design We Need to Rethink

Many everyday products—handwash refills, sauces, detergents, shampoo, mayo—come in flexible refill packs. These usually have:

• a soft pouch body

• a rigid spout or cap

• printed branding layer

• sometimes an inner barrier layer

While they are marketed as “refills” that save plastic, the material reality is more complex.

They often use MLP (multi-layer plastic) with small rigid plastic components. Understanding the system helps us evaluate:

• what is reusable

• what is recyclable

• what is permanently lost to dump yards or co-processing

• what better design alternatives could look like

🧩 Breaking the Pack into Components

🧪 What exactly is MLP?

Multi-layer plastic (MLP) is a sandwich of many materials:

• Plastic (outer)

• Aluminium or metallised film (middle)

• Plastic (inner)

They are bonded using strong adhesives so they behave as one tough film.

Why manufacturers like MLP

• protects flavour, fragrance, moisture content

• increases shelf-life

• lightweight

• cheaper than rigid packaging

• printable for branding

• puncture and leak resistant

Why waste managers dislike MLP

Because the layers cannot be separated economically.

MLP is technically complex and economically unattractive to recycle.
So even when collected, most of it is burnt, co-processed or landfilled.

🥇 The Aluminium Paradox

✔ Aluminium is infinitely recyclable
✔ It does not lose quality on recycling
✔ Almost all aluminium ever produced is still circulating
✔ Recycling aluminium uses only ~5% of the energy needed for new aluminium

BUT in MLP film:

• aluminium is bonded to plastic

• separation is energy-intensive and uneconomical

• so it is not recycled

• it goes to dumpyards, incinerators or cement kilns

So we are:

using an infinitely recyclable, high-value metal
inside
a non-recyclable composite packet

This is one of the starkest examples of design wastefulness.

A material that could stay in circulation forever is instead lost permanently.

♻️ Recycling Potential by Component

1. Rigid cap / spout

Material: HDPE or PP

• recyclable in most cities if segregated

• has established markets

• higher density, easy to capture mechanically

👉 Best part of the pack from a recyclability perspective

2. Flexible MLP pouch body

Material: Plastic + aluminium + adhesive

• cannot be mechanically recycled easily

• pyrolysis exists but is energy heavy

• usually sent to:

  • waste-to-energy

  • co-processing (cement kilns)

  • landfill

👉 Worst part of the pack environmentally

3. The full pack together

When cap and pouch remain attached:

• recyclers reject the whole unit

• mixed materials increase sorting cost

• contamination from product residue adds burden

👉 As a whole unit, recyclability is near zero in practice.

⭐ Sustainability Rating (same structure we used earlier)

(Score out of 5 stars, where 5 = excellent)

🔚 Overall sustainability rating for MLP pouch with cap

⭐⭐ out of ⭐⭐⭐⭐⭐
✔ better than rigid single-use bottles
❌ far worse than mono-material or powder packaging

🧭 Where this packaging does make sense

• where no other barrier system works

• remote supply chains with high transport cost

• short-term transition from rigid to lighter packaging

• emergency relief logistics

🚫 Where we should rapidly move away from it

• where powders or concentrates are feasible

• where reuse / refill systems exist

• where mono-material packaging is possible

• for products that do not need high barrier protection

🌱 Better design directions

• powder formats (like your Godrej Magic example)

• tablet concentrates

• mono-material PE or PP films

• returnable bulk dispensing

• reuse systems

• refill stations instead of packets

• clearly labeled design-for-disassembly caps