Grocery sack

Grocery sacks GROMOS Grotan Grotan BK Grotan ITD2 Grounding... 

The adhesives (qv) used to form tube seams and bag bottoms include unborated dextrin, borated dextrin, casein, latex—casein, latex, poly(vinyl acetate), vinyl acetate copolymers, and hot-melt materials (10,27). Dextrin and casein adhesives are more commonly used in the production of grocery sacks vinyl acetate-type adhesives are commonly used in ah paper multiwah bags. The hot-melt adhesives are typicahy used to tack the phes of the multiwah bag together and to form the seam and bottom joints when polymer film phes or coated paper phes are used in bag constmction. 

Many billions of pounds of polymer are extruded annually into products ranging from household plumbing pipe to thin film grocery sacks, textile fibers to weather stripping. In fact, almost all polymer passes through an extruder at some point, since many polymerization reactors feed extruders in order to include additives and to pelletize. Furthermore, most primary processing... 

Blown film extrusion is perhaps the most widely used extrusion technique, by production volume. Billions of pounds of polyethylene are processed annually by this method to make products such as grocery sacks and trash can liners. In a blown film system (Figure 14-30), the melt is generally extruded vertically upward through an annular die. The thin tube is filled with air as it travels up to a collapsing frame that flattens it before it enters the nip rollers, which pull the film away from the die. The flattened tube then travels over a series of idle rollers to a slitter,... 

A simplified version of the life cycle of grocery sacks is shown below. ... 

Problem adapted from D.T. Allen, N. Bakshani.and K. Rosselot, Pollution Preiention Homework arid Design Problems for Engineering Curricula, American Institute for Pollution Prevention. New York. 1992. The emissions and energy consumption data are from Franklin Associates, Ltd., Resource and Environmental Profile Analysis of Polyethylene and Unbleached Paper Grocery Sacks. Report prepared for the Council for Solid Waste Solutions, Prairie Village, KS, June 1990. 

Energy requirements for polyethylene grocery sacks are 20-40% lower than paper, while generating about 75% less solid waste, 65% less atmospheric emissions and 90% less waterborne waste.12... 

Polyethylene resins, employed in wood-plastic composite materials, typically belong to HDPE, and only in one case (Trex deck boards) it was LDPE (or LDPE/HDPE), originated from grocery sacks and stretch film, used as reclaimed plastic source. 

Council for Solid Waste Solutions Franklin Grocery sacks 1990... 

Fig. 13. Life cycle analysis framework for plastic grocery sacks.

Air Emissions and Energy Requirements for Poi.yf.thyi.ene and Paper Grocery Sacks (Franklin Associates, 1990c)... 

Fig. 15. Energy requirements and atmospheric emissions for paper and plastic grocery sacks, as a function of recycle rate (Franklin Associates, 1990c).

This example has demonstrated that life cycle analyses do not generally result in the identification of an environmentally superior product. In the case of paper and plastic grocery sacks, the plastic sack appears to require... 

Franklin Associates, Ltd., Resource and Environmental Profile Analysis of Polyethylene and Unbleached Paper Grocery Sacks (report prepared for the Council for Solid Waste Solutions)." Franklin Assoc., Prairie Village, KS, 1990c. 

Blown and cast films utilized in flexible packaging applications such as cereal, cracker and snack food packaging, wraps for delicatessen products, and grocery sacks. 

Typical uses for LLDPE include stretch/cling film, grocery sacks, and heavy duty shipping sacks. LDPE and LLDPE are often blended to optimize the benefit ob-... 

The principal applications of HMW-HDPE are in film, pressure pipe, large blow-molded articles, and extruded sheet. HMW-HDPE film now finds application in T-shirt grocery sacks (with 0.6-0.9-mil thick... 

Sclairfilm. Extrusion coatings food packaging, milk cartons, paperboard containers, liner films, stretch films, shrink films, disposables, heavy-duty shipping sacks, and grocery sacks. 

LDPE is more suitable for flexible films than HDPE because it is soft, flexible, and stretchable. LDPE film and sheet applications accounted for 67 % of the total LDPE use worldwide in 2011. The majority of these applications used films instead of sheets. LDPE films were used for bakery products, frozen foods, fresh produce, meat and poultry, and confectionery products. LLDPE is produced as either a homopolymer or a copolymer with 1-10 mol% of a comonomer alkane such as butane, hexane, or octane. This plastic has better properties (e.g., mechanical properties) than LDPE at the same density. It has good clarity, heat-sealing strength, and toughness and is often used for stretch/cling films, grocery sacks, and heavy-duty shipping sacks. 

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