Pilcure ZDBC is mainly used as a non-blooming, non-staining ultra fast primary accelerator or as a booster accelerator in NR / Synthetic rubber latex compounds and dry rubber compounds for the manufacture of transparent / bright colored bloom free rubber products.
Pilcure ZDBC as a primary accelerator is very active above 70°C in NR latex compounds and thus is faster than ZDMC or ZDEC as far as latex compounding is concerned. However; in dry rubber compounds, Pilcure ZDBC is a slower accelerator as compared to ZDMC / ZDEC at equal dosage due to its higher molecular weight. Like other dithiocarbamate accelerators, Pilcure ZDBC exhibits scorching tendency, faster cure rate and higher crosslink density; however, in combination with thiazoles, Pilcure ZDBC produces bloom free vulcanizates having very good ageing resistance in the presence of antioxidants.
In NR latex based compounds, Pilcure ZDBC is effective in the absence of Zinc oxide and thus offers excellent transparency to finished products; however, Zinc oxide and Stearic acid are generally included in dry rubber based compounds as activators of cure at normal dosages. Pilcure ZDBC disperses easily in latex as well as dry rubber based compounds and does not decompose in the absence of sulphur.
Pilcure ZDBC is extensively used in sulphur cure systems designed for curing EPDM rubber based compounds at 1.5 to 3.0 phr levels along with other accelerators such as MBT / TMTD / DPTT to manufacture bloom free products.
Pilcure ZDBC, if required, can be further activated by adding small proportions of dibutyl amine (e.g. for room temperature cure). Pilcure MBTS acts as an effective retarder for Pilcure ZDBC based cure systems without affecting the cure activity at higher curing temperatures.
Pilcure ZDBC is also used as an effective antioxidant in the manufacture of hot melt adhesives (HMAs), thermoplastic elastomers (TPEs), unvulcanized rubber cements and adhesives.
Recommended method for the preparation of 50% dispersion of Pilcure ZDBC for Latex compounding is given below :
|
Ingredients
|
Dry
|
Wet
|
|
Pilcure ZDBC, pbw
|
50
|
50
|
|
10% Dispersing Agent *, pbw
|
1.0
|
10
|
|
10% KOH Solution, pbw
|
0.5
|
5
|
|
China Clay, pbw
|
0.5
|
0.5
|
|
Water, pbw
|
-
|
34.5
|
|
Total
|
52
|
100
|
|
* Sodium salt of polymerized alkyl naphthalene sulfonic acid type.
|
METHOD:
Charge Pilcure ZDBC and dry grind for 2 – 3 hr. Add dispersing agent, part quantity of water and grind to paste. Add china clay, balance quantity of water and 10% KOH solution and ball mill for 24 – 48 hr.
LATEX COMPOUNDING:
Pilcure ZDBC is widely used for the manufacture of NR/SR latex based products such as Surgical Gloves, Condoms, Latex Threads, Prevulcanized Latex, for transparent goods and heat resistant products, High transparency Teats and rubber bands, NR-latex bonded Sports surfaces, Balloons, etc.
DRY RUBBER COMPOUNDING:
Pilcure ZDBC is used in the manufacture of NR / IR based transparent molded products, bright white / bright colored rubber products, Footwear, Cut threads, Transparent tubings, Rubberized fabric, Rubber adhesives and cements, etc. and as a secondary accelerator for the manufacture of bloom-free EPDM and NR-EPDM blend based Molded and Extruded rubber goods.
TYPICAL DOSAGES:
Typical dosages of Pilcure ZDBC based cure systems are given below:
|
TYPICAL DOSAGES OF PILCURE ZDBC
|
|
Product
|
Rubber
|
Accelerator / Sulphur, phr
|
|
ZDBC
|
ZMBT
|
TMTD
|
DPTT
|
TETD
|
ETU
|
S
|
|
Latex Products :
|
|
Latex Thread:
General purpose
Heat resistant
|
NR Latex
|
0.25
1.5
|
1.5
1.8
|
-
-
|
-
1.8
|
-
-
|
-
|
1.7
-
|
|
Surgical Gloves:
Disposable
Sterilizable
|
NR Latex
|
0.75
1.0
|
-
-
|
-
0.5
|
-
|
-
|
-
|
0.5
0.25
|
|
Condoms:
Wet Strip
Dry Strip
|
NR Latex
|
0.8
0.6
|
0.8
1.2
|
-
|
-
|
-
|
-
|
0.8
1.0
|
|
PV Lattices:
Transparent goods
Heat resistant goods
|
NR Latex
|
0.5
1.0
|
-
-
|
-
|
-
|
-
2.5
|
-
1.0
|
1.0
-
|
|
High transparency teats
|
NR Latex
|
1.0
|
-
|
-
|
-
|
-
|
-
|
1.0
|
|
Rubber Bands
|
NR Latex
|
0.75
|
-
|
-
|
-
|
-
|
-
|
0.75
|
|
|
Transparent Balloons
|
NR Latex
|
0.75
|
-
|
-
|
-
|
-
|
-
|
0.75
|
|
|
Latex Bonded Sports- Surface
|
NR Latex
|
1.5
|
1.5
|
-
|
-
|
-
|
-
|
1.6
|
|
|
Dry Rubber Products :
|
|
|
Non blooming Molded and Extruded Goods
|
EPDM
|
2.0-2.5
2.0-2.5
1.0
|
-
1.0
-
|
0.5
1.5
2.0
|
0.8
1.0
0.8
|
-
-
0.8
|
-
1.0
-
|
2.0
1.8
2.0
|
|
|
NR-EPDM Blend (80:20)
|
NR-EPDM
|
0.7-1.0
|
-
|
1.7
|
-
|
-
|
-
|
1.2
|
|
|
Transparent Products
|
NR, IR
|
0.5-0.7
|
-
|
-
|
-
|
-
|
-
|
1.2-1.5
|
|
|
Colored Molded Products
|
NR
SBR
|
0.6
0.75
|
-
|
0.2-0.3
0.2-0.3
|
-
-
|
-
|
-
|
2.0
1.8
|
|
|
Rubberized Fabric
|
NR
|
0.6
|
-
|
0.4
|
-
|
-
|
-
|
1.8
|
|
|
Self curing Adhesives /
Cements
(Two component system)
|
NR
|
2.0-4.0
|
-
|
-
|
-
|
-
|
-
|
1.0
|
|
|
As antioxidant in HMA, TPEs
|
-
|
0.2-0.3
|
-
|
-
|
-
|
-
|
-
|
-
|
|
|
As antioxidant in unvulcanized adhesives / solutions
|
-
|
0.5
|
-
|
-
|
-
|
-
|
-
|
-
|
|