Coffee-scented Cafè "pebbles" from Eastman Chemical Co., Kingsport, Tenn., are palmed-sized samples that let designers evaluate tactile feel as well as scent options available with fragranceenhanced-Tenite cellulosic polymers.


Kingsport, Tenn . . . . On your next trip to the store you may smell what you are looking for before you see it. What are called cellulosic plastics can be used to encapsulate fragrance. Eastman Chemical Co. (eastman.com), in collaboration with Rotuba Extruders, Linden, N.J. (rotuba.com), is using the idea in its Eastman Cafè — a coffeescented, multicolored, "pebble." The palm-of-your-hand-sized samples are available scented, unscented, and in a wide variety of colors. They let designers evaluate the polymer's unique tactile feel as well as scented qualities.

Rotuba is the exclusive compounder of scented cellulosics and developed this technology more than 20 yr ago. Each pebble features two fitted halves. This lets designers mix and match an array of colors and fragrance options.

"Freshly brewed coffee aroma is distinctive and appealing to many people," says Gaylon White, manager of Eastman's design industry program. "With this in mind, we created the Cafè pebble to demonstrate how smell can enhance the shopping experience while stimulating desire for food products."

Scent-encapsulation technology represented by the Cafè pebble can easily be applied to packaging. In fact, that's the driving force behind the pebble, says Eastman. It will let consumers smell the product before purchase. The technology can also be applied to packaging films. Cellulosic polymers are primarily derived from wood pulp. In the form of cellulose acetate, a preferred material for eye and sunglass frames, they are well suited for use in scented plastics. That's because a primary component of these polymers is similar to that used to make most fragrances and aromas.

Eastman's Tenite cellulosics are noted for their balance of properties — toughness, hardness, strength, surface gloss, clarity, and a warm feel. Mechanical properties can be tailored depending on plasticizer levels. Low plasticizer content yields harder surfaces, higher heat resistance and tensile strengths, greater rigidity, and better dimensional stability. Higher plasticizer content boosts impact strength. The polymers come in natural, clear, selected ambers, smoke transparents, and black translucent colors. And they meet FDA requirements for certain food-contact applications when supplied in specific FDA color numbers.

GENERAL PROPERTY RANGE FOR SCENTED POLYMERS
 
CA (CELLULOSE ACETATE)
CAP (CELLULOSE ACETATE PROPIONATE)
CAB (CELLULOSE ACETATE BUTYRATE)
Light transmission, %
>90
>90
>90
Flex modulus, 105 psi
2.3 to 3.9
1.4 to 2.8
1.2 to 2.6
Notched Izod, ft-lb/in.
2.6 to 4.2
3.4 to 10+
3.1 to 8.4
Hardness, R scale
60 to 106
65 to 95
60 to 95
Deflection temperature, °F, (66 psi)
165 to 200
176 to 200
155 to 200
Custom formulations for scented cellulose-based polymers from Rotuba are available using Eastman raw materials.