PE grades have improved processability

NOVA Chemicals recently commercialized three new Novapol polyethylene resins — a high-flow MDPE for rotomolding; a HDPE for small part blow molding; and a HDPE grade for corrugated pipe markets.

The new gas-phase medium-density polyethylene hexene rotomolding resin is designed to provide fast cycling for thin-wall applications. It is UV stabilized for outdoor use and has good environmental stress crack resistance.

For blow molding, HB-L354-A has improved melt strength compared with its predecessor, for easier gauge control, improved impact strength and excellent processability on high-speed, multiple-head blow molding lines. It has superior ESCR, an important attribute for bottles in the household and industrial chemical market.

HP-Y353-A for corrugated pipe has a melt index of 0.30 g/10 min. and enhanced stiffness characterisitcs. It displays good melt strength for gauge control and corrugation formation.

NOVA Chemicals Corp.

888/750-4002

HDPE improves moisture barrier while retaining paper-like qualities

Equistar’s Alathon XL5906 high-stiffness film resin has potential in paper replacement applications. The film made from XL5906 has a secant modulus of 170,000 psi, over 40 percent higher than typical HMW HDPE film, with the same thickness. As a result, film made from the resin feels very much like paper.

Tear and dart strength are retained, and the resin also claims an improved moisture barrier, with moisture vapor transmission rates less than that of typical barrier grade resins.

The XL5906 film can be drawn down to a thickness below 0.4 mil. Co-extruded film consisting of the resin and a thin layer of linear low-density polyethylene or low-density polyethylene results in high gloss and contact clarity combined with paper-like stiffness.

Equistar Chemicals 713/652-7300

Weathering stabilizer for colored vinyl siding

Thermolite 400 is a solid organotin carboxylate PVC heat stabilizer that is available in granulated form and offers improved weatherability and processability over conventional tin mercaptide stabilizers. It is an alternative stabilizer for colured vinyl siding, especially in colors that are normally problem performers.

The material has good dynamic stability, which makes it suitable for use in high-output twin-screw capstock extruders.

Other applications for Thermolite 400 include rigid translucent sheet and foamed sheet.

Atofina Canada Inc.

905/827-9841

Hybrid nanocomposite for extruded film or sheet

RTP Company’s lightweight nanocomposite for film or sheet extrusion incorporates organo-clay hybrids into nylon via the compounding process. It only requires a two to eight percent loading to exhibit equivalent or better properties than typical mineral-filled compounds with 20 to 30 percent loadings.

The resulting film or sheet boasts a four-fold improvement in oxygen transmission rate over unfilled nylon 6.

The barrier properties against moisture, gasses and fragrances make them good choices for packaging applications in the cosmetics, food, medical and electronics industries.

Good transparency also aids in viewing thermoformed packaging contents.

Other areas of improvement include a significant gain in heat deflection by over 35C, tensile strength increased by more than a third, and flexural modulus by almost 50 percent.

The material can be used as an alternative when glass-fibre reinforcement cannot be considered due to specific gravity, mold shrinkage, warpage or wear.

RTP Company 800/433-4787.

Weatherable polymers need less pigment

Bayer has improved its Centrex 825 and Centrex 833 weatherable polymers. The color of the natural grades is lighter and more consistent, enabling customers to use less pigment when coloring natural polymers. As well, the viscosity of the polymer has been adjusted, improving the resin’s processabillity.

All other physical properties of Centrex 825 and 833 remain unchanged.

Bayer Inc. 800/668-2554

Antimicrobial additive for household, athletic goods

A new additive technology that inhibits the growth of bacteria can reduce odors and discoloration of plastic parts and clothing. It is suitable for household supplies such as brooms, garbage cans, shower curtains, as well as athletic apparel and fibres.

The additive is available in four formulations pre-dispersed in polypropylene, ethylene vinyl acetate, polyethylene and polystyrene.

Clariant Masterbatches Division 800/265-3773

Medical acrylic has maximum chemical resistance

Cyrolite Med acrylic-based multipolymer compound was developed for medical device applications requiring maximum chemical resistance. The compound is easily processable, transparent, impact modified, and suitable for injection molding a variety of medical device applications.

Properties show no deterioration after sterilization at typical gamma or e-beam irradiation levels. Sterilization with ethylene oxide gas also has no adverse effects.

Typical applications include filter housings, luers, IV connectors and accessories, spikes, cassettes, Y-sites, check valves, pumps, catheter adapters, and caps and funnels for blood filters.

CYRO Canada Inc. 800/387-3464