CA1054287A - Production of light-degradable polymers - Google Patents
Production of light-degradable polymersInfo
- Publication number
- CA1054287A CA1054287A CA190,066A CA190066A CA1054287A CA 1054287 A CA1054287 A CA 1054287A CA 190066 A CA190066 A CA 190066A CA 1054287 A CA1054287 A CA 1054287A
- Authority
- CA
- Canada
- Prior art keywords
- radical
- unsaturated compound
- aryl
- olefinically unsaturated
- polymer
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
- C08K5/00—Use of organic ingredients
- C08K5/01—Hydrocarbons
Landscapes
- Chemical & Material Sciences (AREA)
- Health & Medical Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
- Organic Chemistry (AREA)
- Compositions Of Macromolecular Compounds (AREA)
- Graft Or Block Polymers (AREA)
- Table Devices Or Equipment (AREA)
- Moulding By Coating Moulds (AREA)
- Agricultural Chemicals And Associated Chemicals (AREA)
- Manufacture Of Macromolecular Shaped Articles (AREA)
- Addition Polymer Or Copolymer, Post-Treatments, Or Chemical Modifications (AREA)
Abstract
ABSTRACT OF THE DISCLOSURE
The present invention relates to polymers having a controlled degradation, consisting of a starting polymer which is selected from the group consisting of polyethylene, poly-propylene and ethylene-vinylacetate copolymer, said polymer being added to an olefinically unsaturated compound containing at least two double bonds, having the following general formula:
The present invention relates to polymers having a controlled degradation, consisting of a starting polymer which is selected from the group consisting of polyethylene, poly-propylene and ethylene-vinylacetate copolymer, said polymer being added to an olefinically unsaturated compound containing at least two double bonds, having the following general formula:
Description
lOS4Zt~7 The present invention relates to degradable polymers and to a process for producing them. More particularly the present invention relates to a process for producing thermo-plastic materials which are degradable through the direct action of the sun light.
It is known that the resistance against the atmosphe-ric and microbial agents, one factor which promotes the broad diffusion of the plastic materials particularly in the packing industry, gives rise to the problem of the plastic material waste storing in the natural environment.
In order to overcome the aforesaid drawback some solutions are proposed such as the employment of essentially unstable polymers or the use of additives which let the more common polymers undergo a photodegradation reaction selectively excited by the ultraviolet radiations of the sun spectrum.
In fact, for limited uses in the agricultural field polybutene-l and copolymers, syndiotactic polybutadiene 1-2 and copolymers are commonly used.
On the contrary regarding the plastic materials used for packing which now are the largest source of wastes, the proposed solutions which consist in introducing into commonly used polymers, either by means of copolymerization or additiva-tion, groups photosensitive to near ultraviolet, lead to photooxidation reactions when the polymer is subjected to the direct action of the sun light.
According to the latter solution, styrene copolymers with vinylketons and carbon oxide, and copolymers consisting of ethylene and carbon oxide are usually employed.
In the additive field, it is suggested to use iron dialkyldithio-carbamates or other complexes of transition metals, gamma-pyrone derivatives, alkyl, alkylaryl and aryl ketons and other systems which, generally acting as hydrogen extractors when subjected to the direct action of the sun ~OS4Z87 light, lead to an accelerated photooxidation of the polymer.
Such additives involve remarkable self-delay phenomena and moreover undergo a remarkable activity decrease when the additive is alkylated or grafted to the polymer in order to reduce its migration.
It has now been found, and it is a first object of the present invention, that it is possible to overcome the aforesaid drawbacks when using olefinically unsaturated compounds containing systems of two or more double bonds, preferably conjugated, in the production of polymers having a controlled degradation which therefore, constitute a second object of the present invention; the conjugated double bonds may also be conjugated with aromatic residuals.
The improved process fundamentally consists in adding to starting polymers which are selected from the group consisting of polyethylene, polypropylene and ethylenevinyl-acetate copolymer, containing or not commercial additives already commonly used as antioxidants, softening agents, anti-static agents or other ones, an olefinically unsaturated 20 compound containing at least two double bonds, preferably conjugated, having the following general formula:
f = c (A)p - / - (C = C) ~ ~ n ~ (B) - C = f Rl R8 1~ R2, R3, R4, R5, R6, R7 and R8, the same or dirrerent may be a hydrogen atom, and alkyl, aryl, cycloalkyl arylalkyl, or alkylaryl radical; at least one of them together with an adjacent radical are divalent radicals which form a ring also containing unsaturations, which may be conjugated with the unsaturations already present, A and B are divalent alkyl, aryl, cycloalkyl, arylalkyl or alkylaryl radicals, p and q being 0 or 1 n may be 0 or an integer ranging 1 to 12 ~ - 2 -1(~54~7 however it is always zero providing that no R ra~iical represents an aryl radical.
Examples of olefinically unsaturated c~mpounds which may be used according to the inventive process are hereinafter re-, . ,~ . .:, . . . . . . .
, :. - -~ ., -. -.,, . . - . ,, , : : . . . . . -. . . ' . '. , ' . :, ' .: , ported: ~054ZB7 1) 1,6-diphenylhexatriene (1,6 DPHT), and
It is known that the resistance against the atmosphe-ric and microbial agents, one factor which promotes the broad diffusion of the plastic materials particularly in the packing industry, gives rise to the problem of the plastic material waste storing in the natural environment.
In order to overcome the aforesaid drawback some solutions are proposed such as the employment of essentially unstable polymers or the use of additives which let the more common polymers undergo a photodegradation reaction selectively excited by the ultraviolet radiations of the sun spectrum.
In fact, for limited uses in the agricultural field polybutene-l and copolymers, syndiotactic polybutadiene 1-2 and copolymers are commonly used.
On the contrary regarding the plastic materials used for packing which now are the largest source of wastes, the proposed solutions which consist in introducing into commonly used polymers, either by means of copolymerization or additiva-tion, groups photosensitive to near ultraviolet, lead to photooxidation reactions when the polymer is subjected to the direct action of the sun light.
According to the latter solution, styrene copolymers with vinylketons and carbon oxide, and copolymers consisting of ethylene and carbon oxide are usually employed.
In the additive field, it is suggested to use iron dialkyldithio-carbamates or other complexes of transition metals, gamma-pyrone derivatives, alkyl, alkylaryl and aryl ketons and other systems which, generally acting as hydrogen extractors when subjected to the direct action of the sun ~OS4Z87 light, lead to an accelerated photooxidation of the polymer.
Such additives involve remarkable self-delay phenomena and moreover undergo a remarkable activity decrease when the additive is alkylated or grafted to the polymer in order to reduce its migration.
It has now been found, and it is a first object of the present invention, that it is possible to overcome the aforesaid drawbacks when using olefinically unsaturated compounds containing systems of two or more double bonds, preferably conjugated, in the production of polymers having a controlled degradation which therefore, constitute a second object of the present invention; the conjugated double bonds may also be conjugated with aromatic residuals.
The improved process fundamentally consists in adding to starting polymers which are selected from the group consisting of polyethylene, polypropylene and ethylenevinyl-acetate copolymer, containing or not commercial additives already commonly used as antioxidants, softening agents, anti-static agents or other ones, an olefinically unsaturated 20 compound containing at least two double bonds, preferably conjugated, having the following general formula:
f = c (A)p - / - (C = C) ~ ~ n ~ (B) - C = f Rl R8 1~ R2, R3, R4, R5, R6, R7 and R8, the same or dirrerent may be a hydrogen atom, and alkyl, aryl, cycloalkyl arylalkyl, or alkylaryl radical; at least one of them together with an adjacent radical are divalent radicals which form a ring also containing unsaturations, which may be conjugated with the unsaturations already present, A and B are divalent alkyl, aryl, cycloalkyl, arylalkyl or alkylaryl radicals, p and q being 0 or 1 n may be 0 or an integer ranging 1 to 12 ~ - 2 -1(~54~7 however it is always zero providing that no R ra~iical represents an aryl radical.
Examples of olefinically unsaturated c~mpounds which may be used according to the inventive process are hereinafter re-, . ,~ . .:, . . . . . . .
, :. - -~ ., -. -.,, . . - . ,, , : : . . . . . -. . . ' . '. , ' . :, ' .: , ported: ~054ZB7 1) 1,6-diphenylhexatriene (1,6 DPHT), and
2) 5-phenyl-1,3-pentadiene.
Without entering the reaction mechanism we think that the additives employed in the inventive process make it possible to photosensitive the activation of molecular oxygen as main factor of the accelerated degradation of the thermoplastic polymers in the presence of sun light.
The process is carried out by adding to the plastic material containing the commercial additive the abovesaid unsatu-rated compound in an amount up to 3%, preferably ranging from 0.1 to 1% by weight.
The additive may be introduced into the polymer according to the known techniques as, for instance, dust mixing and mastication. The operative particularities will be more evident in the light of the following examples, described only for better illustrating the invention without limiting the purposes thereof.
Commercial high density polyethylene, containing ~ little amounts of antioxidants, antistatic agents and other - usual ingredients, was added to 1,6 diphenylhexatriene, according to known methods, in amounts of 0.1, 1 and 3 g per 100 g of polymer.
The films were obtained ~y melting in a press CARVER
heated at 200 C; samples were obtained having a thickness of about 0.02 cm. Such films were su~jected to radiations of a high pressure xenon lamp which showed spectrum energy similar to the sun light one.
The degradation rate was controlled by means of the infra-red spectroscopy by measuring the area of the bands from 1054Z~37 5.65 to 6 characteristic of the carboxyl groups, whose appearance in the polymer is to be correlated to the loss of physical and mechanical properties thereof.
For that purpose, a calibration curve was set up by using stearone as standard sample: the C0 number per gram of po-lymer was plotted showing the ratio between the area of the bands from 5.65 and 6 and the film thickness. During the fllms exposu-re the temperature was kept constant at 29-32C.
The following table reports the results obtained from exposures of a treated and an untreated polymer to the xenon lamp.
Samples C0 number/g Pol. 105 after the following hours of exposure at 29-32C.
Polyethylene (PE) 0 28 60 90 without any additive 0 1.2 2.2 2.6 Polyethylene + 1.6-di-phenylhexatriene (DPHT) " 0.1% 0 3.4 9.1 9.2 " 1yo 0 6.011.4 13.8 " 3~0 1.2 12.4 23 23.2 ~ he results reported in the table emphasize the higher degradation rate of the polymer added to 1.6-diphenylhexatriene.
Hereinafter, it is reported the MFI value of a polymer with and without additive. It is possible to note the negligible effect of the additive on the viscosity of the melted product.
Samples MFI at 190C
PE without any additive 1.25 PE + DPH~ 0.1% 1.24 PE + DPH~ 1% 1.50 EXAMP~E 2 1.6-diphenylhexatriene was added to commercial low den-sity polyethylene containing small amounts of usual stabilizers in amounts equal to 0.1, 1 and 3 parts per 100 parts of polymer.
The films were obtained and exposed to the xenon lamp as in Example 1.
The degradation rate was followed by the I.R. spec-troscopy and according to the methodology described in the foregoing example. The obtained results are reported in the following table.
Sample C0 number/g Pol. 105 after the following exposure hours at 29-32C.
LD PE without any additive - - - 1.4 LD PE ~
1.6 DPHT 0.1% 0 3.1 7.8 7.9 " + " 1% 0 1S.8 22.6 27.2 " + " 3% 2.2 21 37.4 38.8 Again, this example clearly emphasizes a higher degra-dation rate of the polymers containing 1.6-diphenylhexatriene.
The present example shows the behaviour of a commer-cial ethylene-vinylacetate (VA) copolymer, having 2% of nominal weight, a melt flow index of about 1.1 and a density of 0.9268 at 23C, added to 1.6-diphenylhexatriene (1 g per 100 g of polymer) and exposed to the xenon lamp. The exposed samples were obtained according to the foregoing examples. The degrada-~;~ tion rate of the polymer was correlated with the time necessary for letting same be brittle. The results are reported in the following table:
Sample Time necessary for letting the polymer be brittle PE - VA as such ~ 350 h PE - VA + 1.6 DPIIT 1% 220 h The lower time necessary for letting the polymer ad-ded to 1.6-diphenylhexatriene be brittle shows a higher degrada-tion rate thereof.
1054Z~7 ~XAMPLE 4 Some ~ilms of commercial polypropylene (PP), containingor not 1.6-diphenylhexatriene and obtained as the samples of the foregoing examples, were sub~ected to the radiations of the high pressure xenon lamp. The polymer degradation rate was controlled by the I.R. spectroscopy. A calibration curve was set up by using stearone as standard according to example 1. Hereinafter, it is reported the times necessary for letting the polymers be brittle.
Samples Time necessary for letting the polymers be brittle PP as such ~ 110 h PP ~ 1.6 DPHT 1% 60 h The degradation rate was higher for the polymer containing 1.6-diphenylhexatriene.
A
, ~, ~ ' .
Without entering the reaction mechanism we think that the additives employed in the inventive process make it possible to photosensitive the activation of molecular oxygen as main factor of the accelerated degradation of the thermoplastic polymers in the presence of sun light.
The process is carried out by adding to the plastic material containing the commercial additive the abovesaid unsatu-rated compound in an amount up to 3%, preferably ranging from 0.1 to 1% by weight.
The additive may be introduced into the polymer according to the known techniques as, for instance, dust mixing and mastication. The operative particularities will be more evident in the light of the following examples, described only for better illustrating the invention without limiting the purposes thereof.
Commercial high density polyethylene, containing ~ little amounts of antioxidants, antistatic agents and other - usual ingredients, was added to 1,6 diphenylhexatriene, according to known methods, in amounts of 0.1, 1 and 3 g per 100 g of polymer.
The films were obtained ~y melting in a press CARVER
heated at 200 C; samples were obtained having a thickness of about 0.02 cm. Such films were su~jected to radiations of a high pressure xenon lamp which showed spectrum energy similar to the sun light one.
The degradation rate was controlled by means of the infra-red spectroscopy by measuring the area of the bands from 1054Z~37 5.65 to 6 characteristic of the carboxyl groups, whose appearance in the polymer is to be correlated to the loss of physical and mechanical properties thereof.
For that purpose, a calibration curve was set up by using stearone as standard sample: the C0 number per gram of po-lymer was plotted showing the ratio between the area of the bands from 5.65 and 6 and the film thickness. During the fllms exposu-re the temperature was kept constant at 29-32C.
The following table reports the results obtained from exposures of a treated and an untreated polymer to the xenon lamp.
Samples C0 number/g Pol. 105 after the following hours of exposure at 29-32C.
Polyethylene (PE) 0 28 60 90 without any additive 0 1.2 2.2 2.6 Polyethylene + 1.6-di-phenylhexatriene (DPHT) " 0.1% 0 3.4 9.1 9.2 " 1yo 0 6.011.4 13.8 " 3~0 1.2 12.4 23 23.2 ~ he results reported in the table emphasize the higher degradation rate of the polymer added to 1.6-diphenylhexatriene.
Hereinafter, it is reported the MFI value of a polymer with and without additive. It is possible to note the negligible effect of the additive on the viscosity of the melted product.
Samples MFI at 190C
PE without any additive 1.25 PE + DPH~ 0.1% 1.24 PE + DPH~ 1% 1.50 EXAMP~E 2 1.6-diphenylhexatriene was added to commercial low den-sity polyethylene containing small amounts of usual stabilizers in amounts equal to 0.1, 1 and 3 parts per 100 parts of polymer.
The films were obtained and exposed to the xenon lamp as in Example 1.
The degradation rate was followed by the I.R. spec-troscopy and according to the methodology described in the foregoing example. The obtained results are reported in the following table.
Sample C0 number/g Pol. 105 after the following exposure hours at 29-32C.
LD PE without any additive - - - 1.4 LD PE ~
1.6 DPHT 0.1% 0 3.1 7.8 7.9 " + " 1% 0 1S.8 22.6 27.2 " + " 3% 2.2 21 37.4 38.8 Again, this example clearly emphasizes a higher degra-dation rate of the polymers containing 1.6-diphenylhexatriene.
The present example shows the behaviour of a commer-cial ethylene-vinylacetate (VA) copolymer, having 2% of nominal weight, a melt flow index of about 1.1 and a density of 0.9268 at 23C, added to 1.6-diphenylhexatriene (1 g per 100 g of polymer) and exposed to the xenon lamp. The exposed samples were obtained according to the foregoing examples. The degrada-~;~ tion rate of the polymer was correlated with the time necessary for letting same be brittle. The results are reported in the following table:
Sample Time necessary for letting the polymer be brittle PE - VA as such ~ 350 h PE - VA + 1.6 DPIIT 1% 220 h The lower time necessary for letting the polymer ad-ded to 1.6-diphenylhexatriene be brittle shows a higher degrada-tion rate thereof.
1054Z~7 ~XAMPLE 4 Some ~ilms of commercial polypropylene (PP), containingor not 1.6-diphenylhexatriene and obtained as the samples of the foregoing examples, were sub~ected to the radiations of the high pressure xenon lamp. The polymer degradation rate was controlled by the I.R. spectroscopy. A calibration curve was set up by using stearone as standard according to example 1. Hereinafter, it is reported the times necessary for letting the polymers be brittle.
Samples Time necessary for letting the polymers be brittle PP as such ~ 110 h PP ~ 1.6 DPHT 1% 60 h The degradation rate was higher for the polymer containing 1.6-diphenylhexatriene.
A
, ~, ~ ' .
Claims (8)
1. Process for producing polymers which are degrad-able through the direct action of the sun light, comprising adding to a starting polymer which is selected from the group consisting of polyethylene, polypropylene and ethylene-vinyl-acetate copolymer containing or not commercial additives, and olefinically unsaturated compound containing at least two double bonds, and having the following general formula:
wherein R1, R2, R3, R4, R5, R6, R7 and R8, identical or different, represent a hydrogen atom, an alkyl, aryl, cyclo-alkyl, arylalkyl, or an alkylaryl radical; A and B are divalent alkyl, aryl, cycloalkyl, arylalkyl or alkylaryl radicals, p and q are 0 or 1; n is 0 or an integer ranging from 1 to 12;
n being always zero when no R radical is an aryl radical.
wherein R1, R2, R3, R4, R5, R6, R7 and R8, identical or different, represent a hydrogen atom, an alkyl, aryl, cyclo-alkyl, arylalkyl, or an alkylaryl radical; A and B are divalent alkyl, aryl, cycloalkyl, arylalkyl or alkylaryl radicals, p and q are 0 or 1; n is 0 or an integer ranging from 1 to 12;
n being always zero when no R radical is an aryl radical.
2. Process according to claim 1, characterized in that the olefinically unsaturated compound is conjugated.
3. Process according to claim 1, characterized in that the olefinically unsaturated compound is added to said starting polymer in amounts up to 3% by weight.
4. Process according to claim 1, characterized in that the olefinically unsaturated compound is added to said starting polymer in amounts ranging from 0.1 to 1% by weight.
5. Process according to claim 1, characterized in that the unsaturated compound is selected from the group consisting of 1,6-diphenylhexatriene and 5-phenyl-1,3 pentadiene.
6. Polymers having a controlled degradation consisting of a starting polymer which is selected from the group consisting of polyethylene, polypropylene and ethylene-vinylacetate copolymer, said polymer being added to an olefinically unsaturated compound containing at least two double bonds, having the following general formula:
wherein R1, R2, R3, R4, R5, R6, R7 and R8, identical or different, represent a hydrogen atom, an alkyl, aryl, cycloalkyl, arylalkyl, or alkylaryl radical; A and B are divalent alkyl, aryl, cycloalkyl, arylalkyl or alkylaryl radicals, p and q are 0 or l; n is 0, or an integer ranging from 1 to 12, n being always zero when no R
radical is an aryl radical.
wherein R1, R2, R3, R4, R5, R6, R7 and R8, identical or different, represent a hydrogen atom, an alkyl, aryl, cycloalkyl, arylalkyl, or alkylaryl radical; A and B are divalent alkyl, aryl, cycloalkyl, arylalkyl or alkylaryl radicals, p and q are 0 or l; n is 0, or an integer ranging from 1 to 12, n being always zero when no R
radical is an aryl radical.
7. Polymers according to claim 6, characterized in that the olefinically unsaturated compound is conjugated.
8. Polymers according to claim 6, characterized in that the unsaturated compound is selected from the group consisting of 1,6-diphenylhexatriene and 5-phenyl-1,3 pentadiene.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| IT19199/73A IT978147B (en) | 1973-01-15 | 1973-01-15 | PROCEDURE FOR MAKING THE POLYMERS AND POLYMERS SO OBTAINED DEGRADABLE |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1054287A true CA1054287A (en) | 1979-05-08 |
Family
ID=11155729
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA190,066A Expired CA1054287A (en) | 1973-01-15 | 1974-01-14 | Production of light-degradable polymers |
Country Status (17)
| Country | Link |
|---|---|
| JP (1) | JPS542223B2 (en) |
| AT (1) | AT323430B (en) |
| BE (1) | BE809719A (en) |
| CA (1) | CA1054287A (en) |
| CH (1) | CH603731A5 (en) |
| CS (1) | CS186781B2 (en) |
| DD (1) | DD110282A5 (en) |
| DK (1) | DK136614B (en) |
| FR (1) | FR2213949B1 (en) |
| GB (1) | GB1437100A (en) |
| HU (1) | HU167171B (en) |
| IT (1) | IT978147B (en) |
| LU (1) | LU69159A1 (en) |
| NL (1) | NL174056C (en) |
| NO (1) | NO140065C (en) |
| YU (1) | YU35781B (en) |
| ZA (1) | ZA74182B (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2016172699A1 (en) | 2015-04-24 | 2016-10-27 | International Flavors & Fragrances Inc. | Delivery systems and methods of preparing the same |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4399251A (en) * | 1981-12-07 | 1983-08-16 | General Electric Company | Compositions comprising a thermoplastic resin and an olefin mold release agent |
| US6126682A (en) | 1996-08-13 | 2000-10-03 | Oratec Interventions, Inc. | Method for treating annular fissures in intervertebral discs |
| GB0307615D0 (en) * | 2003-04-02 | 2003-05-07 | Ucb Sa | Authentication means |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2924584A (en) * | 1956-06-20 | 1960-02-09 | Du Pont | Composition comprising polyethylene and an ethylenically unsaturated aliphatic hydrocarbon of 20-35 carbon atoms and article thereof |
-
1973
- 1973-01-15 IT IT19199/73A patent/IT978147B/en active
- 1973-12-27 NO NO4946/73A patent/NO140065C/en unknown
- 1973-12-31 GB GB6019373A patent/GB1437100A/en not_active Expired
-
1974
- 1974-01-10 ZA ZA740182A patent/ZA74182B/en unknown
- 1974-01-10 FR FR7400773A patent/FR2213949B1/fr not_active Expired
- 1974-01-14 CA CA190,066A patent/CA1054287A/en not_active Expired
- 1974-01-14 CS CS7400000225A patent/CS186781B2/en unknown
- 1974-01-14 DK DK17074AA patent/DK136614B/en not_active IP Right Cessation
- 1974-01-14 BE BE139787A patent/BE809719A/en not_active IP Right Cessation
- 1974-01-14 JP JP666274A patent/JPS542223B2/ja not_active Expired
- 1974-01-14 AT AT26474A patent/AT323430B/en not_active IP Right Cessation
- 1974-01-14 CH CH47274A patent/CH603731A5/xx not_active IP Right Cessation
- 1974-01-14 HU HUSA2583A patent/HU167171B/hu unknown
- 1974-01-14 YU YU102/74A patent/YU35781B/en unknown
- 1974-01-14 LU LU69159A patent/LU69159A1/xx unknown
- 1974-01-15 NL NLAANVRAGE7400549,A patent/NL174056C/en not_active IP Right Cessation
- 1974-01-15 DD DD176020A patent/DD110282A5/xx unknown
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2016172699A1 (en) | 2015-04-24 | 2016-10-27 | International Flavors & Fragrances Inc. | Delivery systems and methods of preparing the same |
Also Published As
| Publication number | Publication date |
|---|---|
| GB1437100A (en) | 1976-05-26 |
| DE2401568A1 (en) | 1974-08-01 |
| DK136614B (en) | 1977-10-31 |
| DK136614C (en) | 1978-04-10 |
| FR2213949B1 (en) | 1979-03-02 |
| BE809719A (en) | 1974-05-02 |
| NL174056B (en) | 1983-11-16 |
| NL174056C (en) | 1984-04-16 |
| FR2213949A1 (en) | 1974-08-09 |
| DD110282A5 (en) | 1974-12-12 |
| JPS49105838A (en) | 1974-10-07 |
| LU69159A1 (en) | 1974-05-17 |
| NL7400549A (en) | 1974-07-17 |
| NO140065B (en) | 1979-03-19 |
| ZA74182B (en) | 1974-11-27 |
| NO140065C (en) | 1979-06-27 |
| CS186781B2 (en) | 1978-12-29 |
| AU6410574A (en) | 1975-07-03 |
| YU35781B (en) | 1981-06-30 |
| YU10274A (en) | 1980-10-31 |
| JPS542223B2 (en) | 1979-02-03 |
| IT978147B (en) | 1974-09-20 |
| AT323430B (en) | 1975-07-10 |
| HU167171B (en) | 1975-08-28 |
| CH603731A5 (en) | 1978-08-31 |
| DE2401568B2 (en) | 1977-05-18 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| AU602136B2 (en) | Controllably and swiftly degradable polymer compositions and films and other products made therefrom | |
| US3935141A (en) | Environmentally degradable ethylene polymeric compositions | |
| US4121025A (en) | Polymer compositions | |
| JPS63503228A (en) | controlled rheology polypropylene | |
| US4067836A (en) | Environmentally degradable compositions exposed to actinic or ionizing radiation and process | |
| US3825627A (en) | Ethylene polymer composition having enhanced photodegradability | |
| CN101443407A (en) | Polymer article modified with a metal cation containing compound | |
| CA1054287A (en) | Production of light-degradable polymers | |
| US3852227A (en) | Photo-degradable polyolefin resin composition | |
| US5155155A (en) | Photoactivating additive for polymer compositions, in the form of a metal salt of an oxidized wax | |
| KR910003404B1 (en) | Photodegrading agent photo degradable ethylene polymer composition and articles produced there from | |
| US4100334A (en) | Process for rendering polymers degradable and polymers obtained thereby | |
| US3679777A (en) | Photodegradable polyolefins | |
| Scott | The effects of processing on the photooxidation of polymers | |
| US3825626A (en) | Ethylene polymer composition having enhanced photodegradability | |
| US3976621A (en) | Photodegradable copolymers of ethylene and vinyl alcohol containing ketoether groups | |
| US3075950A (en) | Cross-linked olefinic polymers | |
| Baum et al. | Controlled UV degradation in plastics | |
| CA1083283A (en) | Minimizing oil exudation from hydrogenated block copolymer compositions | |
| US4000120A (en) | Process of rendering polymeric material degradable under the direct action of sunlight by the addition of durene | |
| CA1049689A (en) | Photodegradable polymeric compositions having high thermal stability | |
| US4176145A (en) | Photodegradable polymer compositions comprising blends of polymers with ketone-containing block or graft copolymers | |
| CA1076991A (en) | Process | |
| US3549588A (en) | Stabilized polymer compositions containing an organophosphorus sulfide and a benzophenone | |
| JPH07188473A (en) | Agricultural material |