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Learn more about Australian made Alkatuff by clicking on the water tank FAQs below.

Why Buy an Alkatuff Plastic Water Tank?

Poly water tanks are a cost efficient way to store rainwater for domestic, industrial or commercial applications. Plastic rainwater tanks will not only save money in the long run due to lower water bills but are also a great way to help the environment. Plastic rainwater tanks don’t rust and are made in one single piece through a process called rotational moulding.

The raw material used to manufacture your plastic water tank is called polyethylene. Alkatuff is a unique Australian made brand of polyethylene used to develop plastic water tanks to ensure Australian’s are getting the highest quality product from the beginning. Alkatuff is the only Australian made raw material for water tanks so if it’s not an Alkatuff water tank, it’s imported.

Why buy Alkatuff Water Tanks:

  • Alkatuff is tough in the sun and has a UV performance level of UV20 to protect your plastic water tank from the harsh Australian sun. This is more than twice the Australian standard requirement of UV8.
  • C6 as opposed to C4, for toughness and resistance against stress cracking.
  • The Environmental Stress Crack Resistance (ESCR) requirement of the tank standard AS4766 stipulates 500 hours of performance, whilst Alkatuff delivers ESCR performance in excess of 1000 hours. This means that tanks made with Alkatuff holding both chemicals and water will last the distance through superior resistance to stress cracking.
  • Alkatuff has high thermal stability making it less prone to oxidation, discolouration and loss of toughness whilst remaining tolerant of moulding process variation.
  • Alkatuff has been supplied to Australian tank manufacturers for over 20 years and has proven performance in Australian Conditions.
  • Alkatuff polyethylene is supported by local technical service and extensive technical data ensuring the design of your tank can be optimised.
  • Australian made for Australian conditions.

If your tank is not made from Alkatuff, then it’s not Australian made and is likely made from a resin manufactured in Asia or the Middle East and not specifically designed for Australian conditions.

Solar Chart

Proudly Australian made

Alkatuff is the only Australian made poly for water tanks and is made in Botany NSW by Qenos, Australia’s sole manufacturer and leading supplier of world class polyethylene and polymers.

Why choose Alkatuff?

  • UV performance level of UV20 which is more than twice the Australian standard requirement of UV8.
  • Twice the Environmental Stress Crack Resistance (ESCR) requirement of AS4766.
  • Made using a C6 comonomer, rather than the standard C4, for extra strength and resistance against stress cracks.
  • High thermal stability making it less prone to oxidation, discolouration and loss of toughness.
  • Proven track record through supply to Australian tank manufacturers for over 20 years.
  • Purpose made to perform in Australian conditions which is why we say Alkatuff is Tough in the Sun.
  • Alkatuff supports tank manufacturers with local technical service and data to optimise the tank performance and design.

Qenos Botany

The Qenos Botany site covers 37 hectares in a major chemical and plastics manufacturing area located next to Botany Bay shipping terminal. The three major facilities at Botany – Olefines, Alkathene and Alkatuff – produce ethylene, low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE) and high-density polyethylene (HDPE). The polyethylene produced is used across a range of industries and applications including consumer and industrial packaging, water conservation, waste management and agriculture.

Alkatuff is a Linear Low Density Polyethylene resin specially made for the manufacture of poly water tanks. Alkatuff is manufactured by Qenos, Australia’s sole manufacturer and leading supplier of world class polyethylene and polymers. Qenos suppliers Alkatuff resin to compound grinders who add colour to the resin and grind it into powder form suitable for the rotational moulding process. Qenos is not a manufacturer of tanks.

The quality of a rotationally-moulded polyethylene article is highly dependent on the characteristics of the powder particles in regard to their size, shape and size-distribution, in addition to the properties of the polymer grade being used. Alkatuff LLDPE base polymers and compounds are ground in high speed grinding mills to the requirements of the rotational moulding industry. All grades of powder are produced to a manufacturing specification which clearly defines the particle size, the amount of fines present, and the bulk density.

In the rotational moulding process (often called rotomoulding), polyethylene powder is heated in a mould of the shape required to form a hollow moulded article. While the mould and powder are being heated, the mould is rotated simultaneously about two perpendicular axes to distribute the powder evenly over its internal surfaces and to cast a uniform coating of the molten polymer. After cooling the mould, the moulding is removed and the cycle repeated. There are four basic stages to this process, viz. mould charging, mould heating, mould cooling, and demoulding. However, it is the heating and cooling steps which mainly affect the quality of the production.

The standard for UV performance for PE Water Tanks specified in AS/NZS 4766 PE Tanks for the Storage of Chemicals and Water is 8,000 hours of uninterrupted exposure to an intense and specifically developed UV light source. Qenos exhaustively tests the long term UV performance of its Rotational Moulding Resins under conditions of controlled irradiance, chamber temperature and humidity and repeated rain cycles. Alkatuff LL711UV resin achieves a class leading UV performance exceeding 20,000 hours against the required standards, ensuring that tanks made from Alkatuff LL711UV are Tough in the Sun.

When polyethylene is exposed outdoors, the ultra-violet component of the sunlight causes photo-oxidation of the polymer, resulting in surface crazing and a marked deterioration of the mechanical properties with time. Stabilisers are incorporated into the polyethylene to provide weather resistance for outdoor applications. Qenos’ premium tank grade Alkatuff LL711UV achieves a rating of UV20 when tested in accordance with requirements AS/NZS 4766 “Polyethylene storage tanks for water and chemicals”. This far exceeds the minimum requirement of UV8.

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Both Alkatuff LL711UV and LL705UV contain premium UV and antioxidant packages and meet the requirements of the tank standard AS/NZS 4766.

Where very long UV life spans are required carbon black may be incorporated at 2 – 2.5 w/w%. The type and dispersion of carbon black via compounding are important in achieving the best result.

Qenos is Australia’s sole manufacturer and leading supplier of world class polyethylene and polymers. In 2008, Qenos became a subsidiary of China National Bluestar (Group) Co. Ltd, a joint venture between China National Chemical Corporation (ChemChina) and The Blackstone Group, a leading global alternative asset manager and provider of financial advisory services listed on the New York Stock Exchange.

Alkafuff is manufactured by Qenos in Botany NSW.

The Qenos Botany site covers 37 hectares in a major chemical and plastics manufacturing area located next to Botany Bay shipping terminal. The three major facilities at Botany – Olefines, Alkathene and Alkatuff – produce ethylene, low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE) and high-density polyethylene (HDPE). The polyethylene produced is used across a range of industries and applications including consumer and industrial packaging, water conservation, waste management and agriculture.

Qenos adds value to Australia’s rich oil and gas reserves creating innovative products that promote sustainability across Australian industries. Every day in our homes, factories and farms, Australians rely on products made from the polymers and chemicals produced by Qenos. From juice and milk bottles, to mobile garbage bins, water tanks and pipes, to packaging of cleaning products and food. Qenos polymers are everywhere.

Qenos facilities in Melbourne and Sydney draw on technical expertise and productive relationships developed over more than 50 years to deliver solutions for a growing global market. Each year, Qenos contributes more than $1 billion to the Australian economy.

Qenos is proud to be an integral part of Australia’s plastics industry, a major contributor to this nation’s economy, a progressive employer and a safe and responsible member of our local communities.

Alkatuff is an Australian made polyethylene that is specifically engineered for the production of plastic rainwater tanks for Australian conditions. Alkatuff is made with a hexene (C6) comonomer, giving superior impact strength, stress crack resistance and long-term toughness than tanks made with a standard butene (C4) resin.

Alkatuff has more than twice the UV protection specified in the Australian Standard for polyethylene tanks. The Australian Standard for water tanks requires that the material has a UV8 rating while Alkatuff has a rating greater than UV20.

Alkatuff has high thermal stability making it less prone to oxidation, discolouration and loss of toughness making it ideal for use in rotational molded tanks produced for the demands the harsh Australian environment. Make sure your next tank is made from Alkatuff so you can be sure it’s Tough in the Sun.

Why choose Alkatuff?

  • UV performance level of UV20 which is more than twice the Australian standard requirement of UV8.
  • Twice the Environmental Stress Crack Resistance (ESCR) requirement of AS4766.
  • Made using a C6 comonomer, rather than the standard C4, for extra strength and resistance against stress cracks.
  • High thermal stability making it less prone to oxidation, discolouration and loss of toughness.
  • Proven track record through supply to Australian tank manufacturers for over 20 years.
  • Purpose made to perform in Australian conditions which is why we say Alkatuff is Tough in the Sun.
  • Alkatuff supports tank manufacturers with local technical service and data to optimise the tank performance and design.

Alkatuff 100 x 300

Since the early 1990’s, linear low density polyethylene (LLDPE) has come to the fore in rotational  moulding applications, because of their outstanding  physical properties (excellent environmental stress  crack resistance and impact performance) and ease  of processing.

Linear Low Density Polyethylene (LLDPE) refers to low density type polymer with a density between about 0.915 and 0.930 g/cm3, made via an HDPE type manufacturing process. LLDPE is again a linear molecule with a higher level of short chain branching than HDPE (specifically introduced by polymerisation with comonomer), but without the long chain branches which characterise LDPE.

Figure 1-2 general

In linear polyethylenes (mLLDPE, LLDPE, MDPE and some  HDPE grades), the branching in the molecule is achieved  through copolymerisation with comonomers such as  butene-1, hexene-1 or octene-1. These comonomers  respectively give ethyl (C2), butyl (C4) and hexyl (C6)  branches. The degree of branching increases as the  proportion of comonomer in the polymer is increased.  The branching structure will hence depend on the type  and proportion of comonomer, and also the distribution of  comonomer along the molecule (i.e. whether the branches  are evenly distributed or clumped together) and between  molecules. This means that the linear polyethylene grades  supplied by different manufacturers can have noticeably  different properties.

Linear polymers including Alkatuff LLDPE have a lower extensional viscosity and show a much reduced tendency to strain-harden. These differences have important implications in the processing behaviour of these polymers. The lower extensional viscosity means that LLDPE is much easier to draw down to thin gauges.  Because of its lower melt elasticity, LLDPE has much faster relaxation times and gives lower frozen-in orientation than LDPE. In general LLDPE is expected to give greater impact performance than LDPE for a given MFI and density. For a given MFI and density, LLDPE has a much superior environmental stress crack resistance than LDPE. In linear polyethylenes, the distribution and length of the side branches has a profound effect on the environmental stress crack resistance.

C6 is shorthand for the Hexene comonomer used in the Linear Low Density Polyethylene (LLDPE) plastic  from which the water tank is made.

In LLDPE, the branching in the molecule is achieved through copolymerisation with comonomers such as either butene-1 (C4), hexene-1 (C6) or octene-1 (C8). These comonomers respectively give ethyl, butyl and hexyl branches. The toughness of the LLDPE is highly dependent on the short chain branch length, which is determined by the comonomer used. A C6 comonomer has a longer short chain branch length than a C4 comonomer, and so on.

The degree of branching increases as the proportion of comonomer in the polymer is increased. The branching structure will hence depend on the type and proportion of comonomer, and also the distribution of comonomer along the molecule (ie. whether the branches are evenly distributed or clumped together) and between molecules. This means that the LLDPEs supplied by different manufacturers can have noticeably different properties.

In Alkatuff LLDPE, which is a hexene-1 copolymer, the branch points occur every 50 to 100 carbon atoms (10 to 20 methyl groups per 1000 carbon atoms).

Figure 1-3 general

Alkatuff is made with a hexene (C6) comonomer, giving superior impact strength, stress crack resistance and long-term toughness than tanks made with a standard butene (C4) resin.