LATEX FOAM RUBBER (SPONG RUBBER)
[EIRI/EDPR/1079] J.C.: 9723
INTRODUCTION
What is Latex Foam Rubber?
Latex is NOT flexible polyurethane foam. In its natural form, latex is a milky white liquid tapped from the trunks of rubber trees (hevea brasiliensis) and then combined with water to create a thick suspension. In manufacturing natural latex foam rubber, the latex suspension is whipped to a froth and poured into carousel molds, onto a conveyor, or into sheets (for sponge rubber carpet cushion), sometimes additionally frothed using CO2 gas, chilled to below freezing, and then heated to the point of vulcanization (about 240°F). During vulcanization, molecular crosslinks are formed giving the resulting foam rubber the ability to recover its shape after compression. Traditionally, vulcanization is effected by heating the frothed latex suspension while exposing it to elemental sulfur, one or more organic accelerators, a metal oxide (ZnO) and an organic acid (stearic acid). There are many different processing formulations to accommodate different rubber and synthetic rubber blends and there are two different mechanical processing technologies used today. The Dunlop method and the Talalay mechanical process account for all latex foam rubber used in home furnishings products.
What is Synthetic Latex Foam Rubber?
Synthetic latex foam rubber is NOT flexible polyurethane foam. To use the terms “foam rubber” and “polyurethane foam” interchangeably is an injustice to both cushioning products. Synthetic latex foam rubber represents a group of materials manufactured using methods similar to natural latex foam rubber on the same processing equipment. Synthetic latex foam rubber can be the product of natural rubber suspension and rubber substitute blends, or it can be produced using a totally synthetic process such as used to produce styrene-butadiene rubber (SBR) and polymerized chloroprene, known as neoprene, introduced by DuPont in 1932. There is no polyurethane content in natural or synthetic foam rubber and, conversely, no natural or synthetic rubber content in FPF. Today’s synthetic foam rubber can provide many of the physical performance characteristics of natural foam rubber, with more attractive economics. Certain performance attributes can result from the chemical properties of synthetic rubber products. In the case of neoprene, the resulting cushioning product is known for its high degree of fire retardancy. Just as with FPF, latex foam rubber (natural or synthetic) combustion performance can be effected by fire retardant (FR) additives. With FR additives, latex foam rubber cushioning has the ability to meet existing FR requirements for residential, commercial and high risk occupancy applications.
The Economics of Rubber
Rubber production is big business. Dozens of industries worldwide, producing hundreds of different consumer and industrial products, drive the demand for rubber. And natural rubber is an expensive commodity compared to rubber substitutes. The efficiency of the vulcanization process also provides an opportunity to improve production economics. Unfilled vulcanized rubber has superb tear and elongation strength characteristics. In some cases inorganic fillers may be added. In applications, such as for sponge rubber carpet cushion, filler concentration may approach 75% of the final weight of the product. But, just as in FPF, less filler generally results in better performing products.
How Well Does Latex Foam Rubber Cushioning Perform?
Using ASTM testing standards, a number of performance evaluations have been made to compare commercial samples of unfilled latex foam rubber to various grades of FPF. It is not surprising that in most cases latex foam rubber surpassed the physical capabilities of FPF samples. After all, quality latex foam rubber is considered by many experts to be the ultimate high performance cushioning material. Of course, density plays an important role in rubber’s physical performance capabilities. Latex density typically runs 4 pounds per cubic foot and higher. And while premium performance can be achieved with latex, it is accomplished at a premium price.
Latex Foam Rubber and the Environment
Although no unusual environmental issues are associated with the manufacture of all types of latex foam rubber, like most industrial processes, care must be taken with disposal of waste water accumulated from the washing of molded latex foam parts. Latex parts may contain soaps and trace amounts of zinc from the vulcanization process that are released through multiple washings and must be monitored and controlled.
Latex Foam Rubber Recycling
Like FPF, latex foam rubber recovered as manufacturing scrap or recovered from post consumer use can be chopped and utilized when mixed with polyurethane scrap, as bonded carpet cushion. Latex foam rubber generally has a relatively high density and is soft, thus latex foam rubber can only be used in limited amounts in the production of bonded carpet cushion.
COST ESTIMATION
Plant Capacity 1 MT/Day
Land & Building (5000 sq.mt.) Rs. 4.28 Cr
Plant & Machinery Rs. 63.50 Lac
Working Capital for 2 Months Rs. 1.15 Cr
Total Capital Investment Rs. 6.29 Cr
Rate of Return 22%
Break Even Point 54%
CONTENTS
INTRODUCTION
WHAT IS LATEX FOAM RUBBER?
WHAT IS SYNTHETIC LATEX FOAM RUBBER?
THE ECONOMICS OF RUBBER
HOW WELL DOES LATEX FOAM RUBBER CUSHIONING PERFORM?
LATEX FOAM RUBBER AND THE ENVIRONMENT
ABOUT LATEX ALLERGY
USES & APPLICATION
RAW MATERIAL REQUIRED
(A) LATEX
(B) CHEMICAL
VARIOUS FORMULATIONS FOR LATEX FOAM PRODUCTS
B.I.S SPECIFICATION
MARKET SURVEY
APPLICATIONS GALORE
PRODUCTION DECLINES
LOW CONSUMPTION GROWTH
GOOD QUALITY
HIGH PROCESSING COST
PRODUCTS MANUFACTURE
PROCESS OF MANUFACTURE
1) COMPOUNDING AND MATURING
2) FOAMING AND CELLING
3) VULCANISATION:-
4) WASHING AND DRYING
COMMON DEFECTS IN FOAM MAKING
OTHER METHODS OF PREPARATION
LATEX FOAM RUBBER
EXAMPLES 1-24
EXAMPLES 25-28
SYNTHETIC LATEX FOAM RUBBER
EXAMPLE 1
INGREDIENT PARTS/100 PARTS MONOMERS CHARGE FORMULA
EXAMPLE 2
EXAMPLE 3
EXAMPLE 4
EXAMPLE 5
EXAMPLE 6
PREPARATION OF LATEX FOAM RUBBERS AND FILMS
EXAMPLE 1
EXAMPLE 2
EXAMPLE 3
EXAMPLE 4
FLAME-RETARDANT LATEX FOAMS
EXAMPLE 2
PROCESS FOR PRODUCING FOAM RUBBER-BACKED TEXTILES
EXAMPLE 1
EXAMPLE 4
PROCESS AND PLANT FOR MANUFACTURE OF LATEX FOAM PRODUCTS
PROCESS FLOW DIAGRAM FOR THE MANUFACTURE OF LATEX FOAM RUBBER
SUPPLIERS OF RAW MATERIALS
SODIUM SILICO FLOURIDE:
SUPPLIERS OF RUBBER CHEMICALS
SUPPLIER OF EQUIPMENT AND MACHINERY
BOILERS
PRESSURE VESSELS
PLANT & MACHINERY SUPPLIERS FOR RUBBER INDUSTRY
RUBBER VULCANIZER
PRESENT MANUFACTURERS OF LATEX FOAM PRODUCTS
LATEX FOAM MATTRESS
APPENDIX – A:
01. PLANT ECONOMICS
02. LAND & BUILDING
03. PLANT AND MACHINERY
04. OTHER FIXED ASSESTS
05. FIXED CAPITAL
06. RAW MATERIAL
07. SALARY AND WAGES
08. UTILITIES AND OVERHEADS
09. TOTAL WORKING CAPITAL
10. TOTAL CAPITAL INVESTMENT
11. COST OF PRODUCTION
12. TURN OVER/ANNUM
13. BREAK EVEN POINT
14. RESOURCES FOR FINANCE
15. INSTALMENT PAYABLE IN 5 YEARS
16. DEPRECIATION CHART FOR 5 YEARS
17. PROFIT ANALYSIS FOR 5 YEARS
18. PROJECTED BALANCE SHEET FOR (5 YEARS)