Hot melt poly(butylene/ethylene) adhesives

Hot melt adhesives with long open time and good cold metal bonding are made of blends of an at least partially crystalline copolymer of butene-1 and ethylene, an aliphatic, substantially non-polar resin, an antioxidizing agent and, optionally, microcrystalline wax.

BACKGROUND OF THE INVENTION 
This invention relates to hot melt adhesives which exhibit good cold metal 
bonding and a long open time. In particular, this invention relates to hot 
melt butene-1 and ethylene copolymer adhesives. 
Adhesive open time which we are referring to is the maximum time at which 
auto-adhesion (adhesion to itself or to a substrate) can take place for 
material after it is cooled from the melt to room temperature. Hot melt 
adhesives which exhibit a long open time (greater than 20 minutes), as 
well as good cold metal bonding, have long been sought for various 
applications which require a long open time. For example, expansive 
surfaces to be coated by adhesives such as table tops to which formica is 
bonded or assembly line auto parts which are coated with adhesive and 
later contacted with other parts at some point further down the assembly 
line are particularly suited to the use of hot melt adhesives which 
display long open times. Sometimes adhesive coated parts must remain 
uncontacted for as long as several hours, and thus, require longer open 
times than are exhibited by and characteristic of other polymers typically 
used in nonpressure sensitive hot melt adhesives. 
Hot melt adhesives can be formulated to be pressure sensitive and have an 
infinite open time but these adhesives are usually soft, tacky and have 
limited strength and adhesion. Conventional hot melts such as formulations 
of poly(ethylene/vinylacetate), polyethylenes, polyamides, or polyesters 
are rigid, form good strong bonds to certain substrates but have short 
open times usually less than 1 minute. Moreover, these adhesives usually 
have problems in adhearing to cold metal substrates which is often 
required for assembly line production. 
Solvent applied contact adhesives can be formulated to give good bond 
strengths and reasonable open times but they require the use of solvents 
which can be a toxic, a pollutant and a fire hazard. The polybutylene 
adhesives are unique in that they require no solvents, have long open 
times, and show improved adhesion to cold metal substrates. 
The poly-1 butene polymers are a unique group of olefinic polymers because 
they crystallize very slowly. The very slow crystallization rate in 
contrast to the crystallization rates of other polyolefin crystalline 
polymers such as EVAs, polyethylenes and polypropylenes, has been found, 
to be beneficial in formulating hot melt adhesives which have very long 
open times as well as good adhesion and bonding to cold, heat-sink type 
substrates--metals such as stainless steel and anodized aluminum for 
example. 
U.S. Pat. No. 3,573,240 describes hot melt adhesive compositions for hard 
cover book binding. The nature of the book binding process is such that an 
adhesive which rapidly sets and which has an extremely short open time is 
desired. Column 4, lines 1 through 7 of '240 disclose that mirror amounts 
i.e., up to about 5% by weight of alpha olefin comonomers such as ethylene 
and propylene may be present in the butene-1 polymerization system without 
any substantial loss of the desirable properties displayed by the 
resultant essentially homopolymeric system. '240 also states in column 2, 
lines 61 through 63 that the hot melt adhesive products of '240 display 
good heat stability and rapid setting speed. Thus, '240 teaches that even 
though up to about 5% by weight of ethylene may be added to the butene-1 
polymerization system, the polymerization system exhibits rapid setting 
speed (short open time). Thus, '240 is inopposite from the teachings of 
the present invention--that the addition of small amounts of ethylene to 
the butene-1 polymer in combination with certain resins of the present 
invention results in extremely long open time. 
Polybutylene polymers are composed of linear chain molecules with the 
regular and spacially ordered arrangement of ethyl side groups, the 
pendant groups that result when one butene is polymerized across the 1,2 
carbon double bond (along an ethylene chain backbone) (U.S. Pat. No. 
3,362,940. When cooled from melt, the ethyl side groups initially align in 
a tetragonal spatial arrangement, developing a little over one half of the 
ultimate crystallinity (form II). With time, the tetragonal crystalline 
phase transforms into a stable hexagonal spatial arrangement with 
subsequent development of additional crystallinity (form I). This is a 
very slow process, the transformation being completed in the neat polymer 
over a period of several days. 
Butene-1 can be copolymerized with a variety of alpha-olefins to provide 
useful copolymers such as those taught in U.S. Pat. No. 3,362,940. 
Butene-1/ethylene copolymers, with ethylene in the 11-20 mole percent 
range are of special interest in hot melt adhesives, as the ethylene 
comonomer produces a lower glass transition temperature (Tg) amorphous 
phase, reduces further the crystallization rate, and reduces the ultimate 
level of crystallinity in the polymer. Such are advantages in the 
development of long open time melt adhesives, as a lower Tg polymer and a 
higher amorphous phase polymer offers wider formulating latitude in 
combination with compatible resins, waxes, oils, fillers and additives. 
SUMMARY OF THE INVENTION 
It has been surprisingly found that the polybutene-1/ethylene copolymers 
recrystallize slowly where the ethylene content of the copolymers is from 
about 5.5 percent by weight to about 10% by weight, and which copolymers 
are combined with aliphatic substantially non-polar resins, antioxidant 
and an optional amount of a microcrystalline wax. The adhesive 
formulations of the present invention exhibit extremely long open time of 
greater than 20 minutes and in some case greater than 300 minutes (5 
hours). In addition, such hot melt adhesives bond well to cold substrates 
such as stainless steel and anodized aluminum. The adhesives of the 
present invention possess good adhesive strength, are flexible, and have 
low melt viscosities. In addition, the shear adhesion failure temperature 
(SAFT or service temperature) may be controlled to remain sufficiently 
high for the product applications of this invention. 
Other product uses of the adhesive of the present invention include but are 
not limited to use as a contact adhesive for assembly of furniture, 
miscellaneous robot assembly, as an automotive sealant and as an addition 
to atactic polypropylene, to improve open time in bonding.

DETAILED DESCRIPTION OF THE INVENTION 
The copolymer of the present invention is a polybutene-1 copolymer with 
from about 5.5% by weight (11 mole percent) to about 10% by weight (20 
mole percent) polyethylene. Polymers discussed herein are identified as 
H-1 B (homopolymeric 1-butene), 1B-CoE 1.5 (1.5 mole percent coethylene in 
1-butene) and 1B-coE 11.0 (11.0 mole percent coethylene in 1-butene). 
A summary of polybutylene neat polymer properties contrasting homopolymer 
butene-1 with coethylene butene-1 polymers is shown in Table 1a. The 
1-B-coE 1.5 copolymer is the butene-1 ethylene copolymer containing 1.5 
mole percent (0.75 percent by weight) ethylene while the third copolymer 
contains 11.0 mole percent (5.5 percent by weight) ethylene. The Tg of the 
amorphous phase of the 11 mole percent ethylene butene-1 copolymer is 
substantially lower than that of the butylene homopolymer and the 1.5 mole 
percent ethylene butene-1 copolymer. 
Polybutylene with various melt flows or viscosities were produced by mixing 
zero to 1000 ppm of Lupersol 101 peroxide, available from Pennwalt, with 
polybutylene pellets and extruding the mixture through a Brabender 
extruder at 200.degree. C. with an average residence time of 2 minutes. 
TABLE 1a 
______________________________________ 
Physical Properties of Polybutylene Polymers 
Tensile 
Property Tm.sup.(1), 
Tg.sup.(2), 
Yield.sup.(3), 
Tensile/Elongation 
Units .degree.C. 
.degree.C. 
mPa (psi) 
mPa (psi)/% 
______________________________________ 
Hompolymers 
melt index.sup.(4) of 
125 -25 13.8 (2000).sup.(a) 
.sup.(b) /350.sup.(a) 
1.8 to 20.sup.(5) 
1B-coE1.5 
melt index 2.0 
110 -26 11.7 (1700).sup.(a) 
31.0 (4500).sup.(a) /350.sup.(a) 
melt index 100.sup.(5) 
107 -26 11.0 (1600) 
28.3 (4100)/390 
1B-coE11.0 
melt index 0.2 
102 -34 5.52 (800) 
23.7 (3440)/490 
melt index 20.sup.(5) 
100 -34 5.66 (820) 
27.6 (4010)/520 
melt index 99.sup.(5) 
99 -34 5.45 (790) 
21.7 (3150)/480 
______________________________________ 
.sup.(1)(2) Crystalline melting temperature (T.sub.m) and glass transitio 
temperature (Tg) as determined by Differential Scanning Calorimetry. 
.sup.(3) ASTM D638, type "C" die @ 50 cm/minute. 
.sup.(4) ASTM D1238, condition E. 
.sup.(5) Cracked from low melt flow using a Brabender extruder and 
peroxides. 
.sup. (a) Nominal value. 
.sup.(b) Nominal values in a range of 29.0-31.0 mPa (4200-4500 psi). 
To formulate adhesives the butene-1 ethylene copolymer is added to a 
substantially non-polar aliphatic tackifier resin. Included in the 
definition of substantially non-polar are the polyterpene resins. For the 
most part, partially hydrogenated C.sub.9 based hydrocarbon resins, as 
well as C.sub.5 stream resins, and polyterpenes are used in amounts of 
from about 20% by weight to about 60% by weight and preferably 30% to 50% 
by weight. Resins with 85.degree. and 125.degree. C. softening points were 
used (Arkon P-85 and Arkon P-125 respectively). Both show crystalline 
melting points and Tgs above room temperature; T.sub.m =47.degree. C., 
Tg=35.degree. C. for the 85.degree. C. softening point resin, and T.sub.m 
=77.degree. C., Tg=66.degree. C. for the 125.degree. C. softening point 
resin (D.S.C.). Both resins form clear melts and clear solids upon cooling 
in polybutylene polymers. 
The waxes of the present invention are microcrystalline waxes, however, 
paraffinic waxes were used as a contrast with the present invention and 
are identified with corresponding melting points. The waxes are optional 
and may be from about 10% by weight to about 20% by weight of the adhesive 
composition. Shellwax.RTM.500 was used (60.degree. C. and 80.degree. C. 
melting point for comparison of the copolymers) as well as 61.degree. C. 
paraffinic wax. A sufficient amount of the wax, preferably 10% by weight, 
can be used, if desired, to effect a lower viscosity without a substantial 
decrease in service temperature of the adhesive. 
In the examples, a hindered phenolic antioxidant was used. Unless otherwise 
noted, tetrakis methylene (3,5 di-tert-butyl-4-hydroxyhydrocinnamate) 
methane (Irganox.RTM.1010 from Ciba-Geigy) was used at a level of 0.3% by 
weight. Other antioxidants which may be used are Goodrite 3114, Ethanox 
330 and Irganox 1076. 
EXAMPLE I 
Adhesive Preparation 
Adhesives were prepared using either a small Brabender compound head 
(approximately 50 cc capacity) or a one quart sigma blade mixer. The test 
formulations were easily blended using preheated equipment 
(170.degree.-180.degree. C.) by introducing the polybutylene polymer, 
mixing until a soft, homogeneous mass is formed, and then gradually 
introducing the remaining ingredients. Mixing times were 20 minutes. 
EXAMPLE II 
Adhesive Film 
Thin adhesive films (125 to 200 microns) were prepared by casting onto 
release coated polyester film (onto release coated side) using a pair of 
heated nip rolls that are adjusted to produce the desired gap, hence 
adhesive thickness. Preheated adhesive (at about 130.degree. C.) was 
poured onto a polyester film and hand drawn through the heated nip rolls. 
Using this technique, adhesive films a meter in length by 15 centimeters 
in width were produced with a small quantity (&lt;60 gms) of adhesive, so 
that very small quantities of adhesive could be evaluated. 
Once cooled and allowed to set, these adhesives were used to prepare test 
specimens. For example, Kraft paper to Kraft paper bonds were made by 
cutting adhesive squares from the polyesters film, peeling them off, 
placing the adhesive between the paper and heat sealing with a hot bar 
sealer. Alternately, the adhesive square or an adhesive strip may be 
placed on a piece of plastic or metal substrate, melted with a heat gun 
(or in an oven), and then joined under moderate contact pressure to form 
lap shear or SAFT bonded substrate specimens. 
TESTING METHODS 
1. Adhesive Hot Melt Viscosity--Viscosities were measured at 177.degree. C. 
in a Brookfield Thermocell Viscometer with an RVT head and Number 29 
spindle (ASTM D3236); for low viscosity formulations, a number 21 spindle 
was used. 
2. SAFT: Shear Adhesion Failure Temperature--The upper service temperature 
limit of the adhesive was estimated by the SAFT test. A 25.times.25 mm lap 
shear specimen was formed with the substrate of interest, the adhesive as 
the interlayer between the substrate surfaces. In the case of Kraft paper, 
National Bureau of Standards, Standard Reference Material 1810, 
Linerboard, was used. The lap shear specimen was suspended in a 
temperature programmed oven, and the free end of the specimen was loaded 
at 500 or 1000 gm. The temperature was programmed to rise at a rate of 
22.degree. C./hour. The SAFT was taken at the temperature at which the 
bond fails and the weight-load falls. 
Lap Shear Strength--A 25.times.25 mm lap shear specimen was formed with the 
substrate of interest, the adhesive as the interlayer between the 
substrate surfaces. Specimens were drawn apart at a rate of 1.27 mm/min. 
on an Instron tester, and the maximum force required to break the bond was 
recorded. Because the magnitude of force required to break the adhesive 
bonds of crystalline/olefinic polymer based recipes was large, substrates 
chosen for this test were metals. About 0.75 mm thickness (30 mils) mild 
steel or stainless steel were used for testing. 3 mm (125 mils) anodized 
aluminum was also used. 
4. Adhesive Open Time--Open time is defined as the maximum time at which 
auto-adhesion (contact adhesion) can take place for a material which, 
after melting, is brought to room temperature. In our study open time was 
measure by applying test recipes as a hot melt onto two surfaces at 
ambient temperature, waiting the specified time, then pressing the 
surfaces together under moderate pressure (adhesive to adhesive contact). 
Within 10 minutes of this bond formation, the surfaces were pulled slowly 
apart under tension. Bonds that did not fail at the adhesive/adhesive 
interface (as a function of time) marked maximum open time. 
5. Polymer Melt Index--Melt index (abbreviated MI or M.I. throughout) was 
determined according to ASTM D1238, condition E, temperature (190.degree. 
C.) and load (2160 g). These conditions are typically used for EVA and 
polyethylene polymers. 
6. Tm and Tg by Differential Scanning Colorimetry (D.S.C.)--Heating and 
cooling rates were 10.degree. C./minute. Tm is the temperature at which a 
maximum occurs in the crystalline melting caloric peak. For resins, Tg was 
determined by drawing a tangent to the subtle shoulder in the heating 
portion of the D.S.C. cycle, determining the mid-point of this tangent, 
and reading the temperature at this mid point. 
7. Crystallization half times by DSC--The crystallization half time was 
measured using the DSC. The sample was melted in the DSC pans at 
140.degree. C. The temperature was then lowered as quickly as possible to 
the desired temperature. The time for one half of the crystalline phase to 
crystallize was recorded. This usually corresponded to the peak in the 
exotherm time curves since the peaks were nearly symmetrical. 
8. Degree of crystallinity--The degree of crystallinity of the polybutylene 
polymers was determined by intergrating the area under the melting point 
of the DSC curve and thereby determining the number of calories/gm of 
sample that was required to melt the sample. Knowing that pure crystalline 
polybutylene (form I) requires 30 calories/gm to melt, the degee of 
crystallinity can be calculated. 
In formulating the polybutylene adhesives with different tackifying resins 
and different copolymer content polybutylenes, it was observed that the 
brittleness of the adhesive could vary dramatically. For many applications 
it would be desirable to have a more flexible adhesive so the bond would 
be less sensitive to impact. It was found that the brittleness temperature 
could be estimated from the calculated Tg of the amorphous resin of the 
adhesive (amorphous polybutylene and tackifying resin) using the following 
empirical equation for compatible polymeric blends. 
##EQU1## 
where 
##EQU2## 
Tg.sub.r =glass transition resin (.degree.K.) Tg.sub.a =glass transition 
amorphous polybutylene phase (.degree.K.) 
Table 1b shows that the polybutylene adhesive with 11% coethylene is 
advantageous for obtaining a lower Tg product which is less brittle. The 
compromise in achieving these better properties is a slightly lower SAFT 
(.about.10.degree. C.) due the lower crystalline melting point. Naphthenic 
paraffinic oils, paraffinic oils, or rubbers such as ethylene propylene 
rubber, EPDM, ethylene butylene rubber, saturated thermoplastics 
elastomers (KRATON.RTM.G Rubbers), or butyl rubbers can be added to help 
reduce brittleness. Usually only about 10-20% oil can be tolerated or oil 
exudation from the adhesive will occur. 
The viscosity of hot melt adhesives can also be important for good surface 
wetting and ease of application. The polybutylenes are advantageous again 
because they can be adjusted by cracking (decreasing the molecular weight 
with peroxides and temperature) to a wide spectrum of viscosities. 
Moreover, the variation in viscosities has only a nominal affect on final 
properties such as SAFT. 
TABLE 1b 
______________________________________ 
Calculated Tg's of Adhesive/Resin Formulations 
Formu- Tg 
lations M.I. (.degree.C.) 
Cry..sup.(a) 
Am. P. 
A B C D E 
______________________________________ 
H-1-B 123 -25 52% 48% 50 -- -- -- -- 
1B-coE1.5 
80 -26 46% 54% -- 50 -- -- -- 
1B-coE11.0 
99 -34 35% 65% -- -- 50 50 50 
Arkon P-85 
-- 35 yes yes 50 50 50 -- 25 
Arkon P-125 
-- 66 yes yes -- -- -- 50 25 
A.O. -- -- -- -- 0.3 0.3 0.3 0.3 0.3 
______________________________________ 
A B C D E 
______________________________________ 
COM- Brittle Brittle Flexible 
Brittle 
Flexible 
MENT: 
SAFT 92.sup.SS 
88.sup.SS 82.sup.SS /65.sup.K 
84.sup.K 
77.sup.K 
(1 Kg), .degree.C. 
SAFT 75.sup.K 
71.sup.K 
(1/2 Kg), .degree.C. 
Calculated 
55 51 37 64 52 
Tg of ad- 
hesive 
amorphous 
phase, .degree.F. 
______________________________________ 
.sup.a Crystallinity of polybutylene polymers determined by DSC. Melt 
index versus SAFT to Kraft Paper (KP) and Anodized Aluminum (AnAl), the 
relationship between service temperature and melt index, is shown in FIGS 
2A (KraftKraft) and 2B (Anodized AluminumAnodized Aluminum) for a 50/50 
blend of 1BcoE 11.0 polymer/Arkon P85. The upper position curves present 
SAFT test results with a 1/2 kg load; the lower position curves with a 1 
kg load. 
Some drop in service temperature was found as polymer melt index was 
increased on either KP or AnAl substrates. At the lighter load, the 
magnitude is about 5.degree. C. over the 10 M.I. range. At heavier load (1 
kg), the effect is more pronounced on KP--about 11.degree. C. drop over 
the same M.I. span. 
A relatively small difference in SAFT is seen when results are compared 
between substrates; SAFT seems to be slightly lower at a given M.I. on KP 
versus AnAl. 
EXAMPLE III 
TABLE II 
______________________________________ 
Polybutylene Comonomer Content versus 
Selected Adhesive Properties 
A B C 
______________________________________ 
Homopolymer 1-butene, 123 M.I. 
50 -- -- 
1-B-coE1.5, 80 M.I. 
-- 50 -- 
1-B-coE11.0, 99 M.I. 
-- -- 50 
Arkon P-85 50 50 50 
Irganox .RTM. 1010 
0.3 0.3 0.3 
Test Results: 
SAFT.sup.1, .degree.C. 
92 88 82 
Melting point.sup.2, .degree.C. 
123 108 99 
Open time, minutes 
30-40 60-120 &gt;300 
Lap Shear, KN (lbs) 
1 hour -- -- .71 (160) 
1 week -- -- 2.47 (550) 
Flexible/Brittle Brittle Brittle Flexible 
Melt viscosity @ 177.degree. C., Pa s 
20-25 20-25 20-25 
______________________________________ 
.sup.1 1/2 kg load on 25 .times. 25 mm bond area. Cohesive failure was 
noted on all samples. Specimens were prepared by bonding to preheated 
stainless steel @ 180.degree. C. 
.sup.2 Neat polymer, Form I crystalline structure. 
In Table II SAFT, open time, flexibility/brittleness, lap shear strength 
and viscosity were compared for three test recipes based on polybutylene 
polymers with varying comonomer content as 50-50 blends with the Arkon 
P-85. 
The mating substrates were individually coated, then brought together under 
moderate pressure. Such bonds could be accomplished over a period of hours 
after the substrates have been coated. We have found that open time is a 
strong function of the comonomer content of the polymer. This result can 
be explained on the basis of excellent resin compatibility with the 
amorphous phase, amorphous phase level found in each polymer, and the 
slower rate of crystalline transformation found in the higher comonomer 
content polymers. Open time for conventional hot melt adhesives such as 
polyethylene or EVA is on the order of 15-60 seconds. Formulation C, 
polybutene-1 with 11% ethylene, exhibited on open time of more than 300 
minutes and was flexible at room temperature. Lap shear results are of 
interest--a change in adhesive strength was noted with time as the 
polybutylene crystallization occurred. The viscosities measured indicate 
little difference among these polymers at these high (.about.100) melt 
indicies. 
EXAMPLE IV 
Waxes in Polybutylene Adhesive Formulations--Table III summarizes results 
found for test recipes containing wax, either microcrystalline or 
paraffinic. 
TABLE III 
______________________________________ 
Waxes in Polybutylene Adhesive Formulations 
Ref. A B C 
______________________________________ 
1-B-coE 11.0, M.I. 100 
30 30 30 30 
Arkon P-85 70 50 50 50 
60.degree. C. microcrystalline wax 
-- 20 -- -- 
80.degree. C. microcrystalline wax 
-- -- 20 -- 
61.degree. C. paraffinic wax 
-- -- -- 20 
Irganox .RTM. 1010 
0.3 0.3 0.3 0.3 
Test Results: 
SAFT.sup.1, .degree.C. 
1/2 kg load -- 57.degree. C. 
59.degree. C. 
-- 
1 kg load -- 47.degree. C. 
52.degree. C. 
-- 
Flexible/Brittle 
Brittle Flexible Flexi- 
Brittle 
ble 
Melt Viscosity @ 177.degree. C., 
3.4 1.2 1.7 1.0 
Pa .multidot. s 
______________________________________ 
.sup.1 Kraft paper to kraft paper heat seal bond, 25 mm .times. 25 mm 
square, adhesive thickness 100 to 125 microns. 
Microcrystalline wax appears to be a reasonably compatible diluent for 
polybutylene polymers. Note that the effect of softening point of the 
given microcrystalline wax is not reflected strongly in a service 
temperature difference for the finished adhesive. 
Paraffinic wax produces a brittle product. (See formulation C). It would 
appear to be incompatible with either amorphous or crystalline polymer 
phases. 
Microcrystalline wax is also an effective additive to reduce viscosity, as 
seen in formulations A and B. 
TABLE IV 
__________________________________________________________________________ 
Comparison of Hot Melt Adhesive Open Time and Metal Adhesion 
1 2 3 4 5 6 7 
__________________________________________________________________________ 
Eastobond A3 PE Adhesive.sup.(1) 
100 
Amscomelt A132 EVA Adhesive.sup.(2) 
100 
H-1-B (123 MI) 50 
1B-CoE1.5 (.about.80 MI) 50 
1B-CoE11.0 (99 MI) 50 40 30 
Arkon P-85.degree. C..sup.(4) 
50 50 50 50 50 
Shellwax .RTM. 500.sup.(3) 10 20 
Irganox 1010 0.3 
0.3 0.3 0.3 0.3 0.3 0.3 
Open Time (minutes) 
&lt;1 &lt;1 30-40 60-120 
&gt;300 &gt; &gt;20 
Adhesion to cold 
Anodized Aluminum 
No Yes -- -- Yes Yes Yes 
Stainless Steel (316) 
No No -- -- Yes Yes Yes 
Lap Shear.sup.(5) (psi) 
1 hour 615 
540 160 240 
1 week 490 
560 550 330 
SAFT (.degree.F.) 
188 
148 197 190 180 167 141 
Melt Viscosity 2.2 
1.7 46 12 32 
(Pa s, 350.degree. F.) 
Comments brittle 
brittle 
flexible 
flexible 
flexible 
__________________________________________________________________________ 
.sup.(1) Eastman Kodak 
.sup.(2) Union Oil 
.sup.(3) Shell Chemical Company 
.sup.(4) Arwakawa 
.sup.(5) 1" .times. 1 
.sup.(6) 1" .times. 1", 1/2 Kg metal 
As may be seen in Table IV, the only formulations which exhibited both long 
open time as well as cold metal adhesion were numbers 5, 6 and 7, which 
contained 50%, 40% and 30% by weight, respectively, 1B-coE 11.0. Numbers 6 
and 7 also contained 10 and 20% by weight, respectively, of 
Shellwax.RTM.500. Formulations #1 and #2 (polyethylene and 
polyethylene/vinylacetate adhesives) exhibited extremely short open times 
of less than 1 minute, each. Number 1 did not bond to either the aluminum 
or the stainless steel. Number 2 did not bond to the stainless steel. 
Formulations #3 and #4 (PB homopolymer and PB copolymer with 1.5% ethylene 
each mixed with Arkon P-85) exhibited long open time and were brittle. 
Thus, formulations with Arkon P-85 and from about 30% by weight to about 
50% by weight 1B-coE 11.0 and from about 10% by weight to about 20% by 
weight Shellwax.RTM.500 exhibit long open time values, as well as good 
adhesion to cold anodized aluminum and stainless steel and are flexible. 
Most preferably, 50% by weight 1B-coE 11.0 and 50% by weight Arkon P-85 
resin, with about 0.3% antioxidant, yields an open time of greater than 
300 minutes (5 hours) and exhibits good adhesion to cold anodized aluminum 
as well as stainless steel. Such properties allow adhesion on metal 
surfaces with open times on the order of anywhere from several minutes to 
several hours. This is particularly advantageous, for example, in auto 
plant assembly lines where the adhesive is applied to a large metal 
surface area which is not bonded to another piece of equipment until some 
point further down the assembly line. 
Table V studies interactions of resin Tg and polybutylene adhesive 
properties for the 1B-coE 11.0 polymer. 
Composition A employed 50/50 polymer/125.degree. C. softening point (S.P.) 
resin blend. When compared with composition B (lower Tg 85.degree. C. S.P. 
resin) we found that indeed the A formulation was brittle, and thus, not 
as suitable as an adhesive. 
Composition C employed a 50/25-25 combination of polymer and a blend of the 
two resins in equal portions. The composition was flexible and had an 
intermediate service temperature. Thus, the resin Tg plays a crucial role 
in setting the temperature at which a glassy versus compliant adhesive is 
observed. 
When a portion of the polymer was substituted with wax (Compositions D and 
E), a drop in viscosity was achieved, as well as a drop in service 
temperature. In comparing compositions E and B, while both have equally 
good upper service temperatures, composition E has almost a ten-fold 
reduction in hot melt viscosity than composition B. Thus, addition of the 
microcrystalline wax produces a ten-fold decrease in hot melt viscosity, 
while maintaining the service temperature. Even lower viscosity was 
obtained in D (twenty-fold) with a service temperature upper limit of 
57.degree. C. 
TABLE V 
______________________________________ 
Interplay of Resin Tg and Polybutylene Adhesive Properties 
A B C D E 
______________________________________ 
1-B-coE11.0, M.I. 100 
50 50 50 30 30 
Arkon P-85, Tg = 35.degree. C. 
-- 50 25 50 -- 
Arkon P-125, Tg = 66.degree. C. 
50 -- 25 -- 50 
60.degree. C. microcrystalline wax 
-- -- -- 20 20 
Irganox 1010 0.3 0.3 0.3 0.3 0.3 
Test Results: 
SAFT, .degree.C. (1/2 Kg, Kraft) 
84 65 77 57 65 
Flexible/Brittle 
Brit. Flex. Flex. 
Flex. 
Flex. 
Melt Viscosity @ 177.degree. C., 
25 20 26 1.2 2.5 
Pa .multidot. s 
______________________________________ 
Deviations in the above described materials and/or methods may be apparent 
to one of ordinary skill in the art.